Ue operation with reduced power consumption

ABSTRACT

Methods, user equipment (UE), and base stations for reception or transmission of physical downlink control channels (PDCCH) associated with a master node (MN) or with a secondary node (SN) are provided. A method of operating a UE to receive PDCCHs includes receiving an indication for a first number of cells N cells,MCG   cap  and for a second number of cells N cells,SCG   cap ; and determining a first total number of PDCCH candidates on N cells,MCG   DL,μ  cells of the MN over a time period according to N cells,MCG   cap  and a second total number of PDCCH candidates on N cells,SCG   DL,μ  cells of the SN over the time period according to N cells,SCG   cap . μ is a subcarrier spacing (SCS) configuration for an active bandwidth part (BWP) on each of the N cells,MCG   DL,μ  cells or N cells,SCG   DL,μ  cells.

CROSS-REFERENCE TO RELATED APPLICATIONS AND CLAIM OF PRIORITY

The present application claims priority to:

-   -   U.S. Provisional Patent Application Ser. No. 62/730,728, filed        on Sep. 13, 2018;    -   U.S. Provisional Patent Application Ser. No. 62/738,076, filed        on Sep. 28, 2018;    -   U.S. Provisional Patent Application Ser. No. 62/752,528, filed        on Oct. 30, 2018;    -   U.S. Provisional Patent Application Ser. No. 62/791,260, filed        on Jan. 11, 2019; and    -   U.S. Provisional Patent Application Ser. No. 62/841,868, filed        on May 2, 2019. The content of the above-identified patent        document is incorporated herein by reference.

TECHNICAL FIELD

The present application relates generally to wireless communicationsystems and, more specifically, the present application relates tooperation with reduced power consumption for a user equipment (UE) andto transmissions and receptions of physical downlink control channels(PDCCHs) for operation with dual connectivity.

BACKGROUND

The present disclosure relates to a pre-5^(th)-generation (5G) or 5Gcommunication system to be provided for supporting higher data ratesbeyond 4^(th)-generation (4G) communication system such as long-termevolution (LTE). The present disclosure relates to indicating to a UEwhether or not to monitor PDCCH candidates for a number of C-DRX periodsor for a number of PDCCH monitoring occasions within a C-DRX period. Thedisclosure also relates to providing means to a UE to indicate to aserving gNB preferred configurations for transmissions and receptions.The present disclosure further relates to enabling a UE to perform fastactivation and deactivation for a number of secondary cells (SCells).The present disclosure additionally relates to designing new operatingmodes for communication between a UE and a serving gNB that enable UEpower savings without penalizing network operation. The presentdisclosure also relates to adapting a set of slot timing values K1 for aHARQ-ACK codebook determination with respect to a number of activeSCells and a corresponding subcarrier spacing (SCS) configuration. Thepresent disclosure further relates to setting a processing time forscheduling PDSCH/PUSCH and to combining an activation/deactivation ofSCells together with dynamic adaptation on processing time forscheduling. The present disclosure additionally relates to establishinga same understanding among an master node (MN), an secondary node (SN),and a UE for a number of PDCCH candidates that the UE is expected tomonitor per slot and for a number of non-overlapping CCEs that the UE isexpected to able to perform channel estimation per slot.

SUMMARY

The present disclosure relates to a pre-5G or 5G communication system tobe provided for supporting reduced UE power consumption and operationwith dual connectivity beyond a 4G communication system such as LTE.Embodiments of the present disclosure provide transmission structuresand format in advanced communication systems.

In one embodiment, a method for a UE to receive PDCCHs from a MN or froma SNs provided. The method includes receiving an indication for a firstnumber of cells N_(cells,MCG) ^(cap) and for a second number of cellsN_(cells,SCG) ^(cap); and determining a first total number of PDCCHcandidates for N_(cells,MCG) ^(DL,μ) downlink (DL) cells of the MN overa time period according to N_(cells,MCG) ^(cap) and a second totalnumber of PDCCH candidates for N_(cells,SCG) ^(DL,μ) DL cells of the SNover the time period according to N_(cells,SCG) ^(cap). MCG denotes amaster cell group for the MN, SCG denotes a secondary cell group for theSN. μ is a subcarrier spacing (SCS) configuration for an activebandwidth part (BWP) for each of the N_(cells,MCG) ^(DL,μ) DL cells orN_(cells,SCG) ^(DL,μ) DL cells.

In another embodiment, a base station is provided. The base stationincludes a transmitter and a processor operably connected to thetransmitter. The transmitter is configured to transmit an indication fora first number of cells N_(cells,MCG) ^(cap) and for a second number ofcells N_(cells,SCG) ^(cap). The processor is configured to determine anumber of PDCCH candidates M_(PDCCH,MCG) ^(total,μ) for N_(cells,MCG)^(DL,μ) DL cells over a time period according to N_(cells,MCG) ^(cap). μis a SCS configuration for an active BWP for each of the N_(cells,MCG)^(DL,μ) DL cells.

In yet another embodiment, a UE is provided. The UE includes a receiverand a processor operably connected to the receiver. The receiver isconfigured to receive an indication for a first number of cellsN_(cells,MCG) ^(cap) and for a second number of cells N_(cells,SCG)^(cap). The processor is configured to determine a first total number ofPDCCH candidates M_(PDCCH,MCG) ^(total,μ) for N_(cells,MCG) ^(DL,μ) DLcells over a time period according to N_(cells,MCG) ^(cap) and a secondtotal number of PDCCH candidates M_(PDCCH,SCG) ^(total,μ) forN_(cells,SCG) ^(DL,μ) DL cells over the time period according toN_(cells,SCG) ^(cap). MCG denotes a master cell group for a MN and SCGdenotes a secondary cell group for a SN. μ is a SCS configuration for anBWP for each of the N_(cells,MCG) ^(DL,μ) DL cells or N_(cells,SCG)^(DL,μ) DL cells.

Other technical features may be readily apparent to one skilled in theart from the following figures, descriptions, and claims.

Before undertaking the DETAILED DESCRIPTION below, it may beadvantageous to set forth definitions of certain words and phrases usedthroughout this patent document. The term “couple” and its derivativesrefer to any direct or indirect communication between two or moreelements, whether or not those elements are in physical contact with oneanother. The terms “transmit,” “receive,” and “communicate,” as well asderivatives thereof, encompass both direct and indirect communication.The terms “include” and “comprise,” as well as derivatives thereof, meaninclusion without limitation. The term “or” is inclusive, meaningand/or. The phrase “associated with,” as well as derivatives thereof,means to include, be included within, interconnect with, contain, becontained within, connect to or with, couple to or with, be communicablewith, cooperate with, interleave, juxtapose, be proximate to, be boundto or with, have, have a property of, have a relationship to or with, orthe like. The term “controller” means any device, system or part thereofthat controls at least one operation. Such a controller may beimplemented in hardware or a combination of hardware and software and/orfirmware. The functionality associated with any particular controllermay be centralized or distributed, whether locally or remotely. Thephrase “at least one of,” when used with a list of items, means thatdifferent combinations of one or more of the listed items may be used,and only one item in the list may be needed. For example, “at least oneof: A, B, and C” includes any of the following combinations: A, B, C, Aand B, A and C, B and C, and A and B and C.

Moreover, various functions described below can be implemented orsupported by one or more computer programs, each of which is formed fromcomputer readable program code and embodied in a computer readablemedium. The terms “application” and “program” refer to one or morecomputer programs, software components, sets of instructions,procedures, functions, objects, classes, instances, related data, or aportion thereof adapted for implementation in a suitable computerreadable program code. The phrase “computer readable program code”includes any type of computer code, including source code, object code,and executable code. The phrase “computer readable medium” includes anytype of medium capable of being accessed by a computer, such as readonly memory (ROM), random access memory (RAM), a hard disk drive, acompact disc (CD), a digital video disc (DVD), or any other type ofmemory. A “non-transitory” computer readable medium excludes wired,wireless, optical, or other communication links that transporttransitory electrical or other signals. A non-transitory computerreadable medium includes media where data can be permanently stored andmedia where data can be stored and later overwritten, such as arewritable optical disc or an erasable memory device.

Definitions for other certain words and phrases are provided throughoutthis patent document. Those of ordinary skill in the art shouldunderstand that in many if not most instances, such definitions apply toprior as well as future uses of such defined words and phrases.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure and itsadvantages, reference is now made to the following description taken inconjunction with the accompanying drawings, in which like referencenumerals represent like parts:

FIG. 1 illustrates an example wireless network according to embodimentsof the present disclosure;

FIG. 2 illustrates an example gNB according to embodiments of thepresent disclosure;

FIG. 3 illustrates an example UE according to embodiments of the presentdisclosure;

FIG. 4 illustrates an example transmitter structure using OFDM accordingto embodiments of the present disclosure;

FIG. 5 illustrates an example receiver structure using OFDM according toembodiments of the present disclosure;

FIG. 6 illustrates an example encoding process for a DCI formataccording to embodiments of the present disclosure;

FIG. 7 illustrates an example decoding process for a DCI format for usewith a UE according to embodiments of the present disclosure;

FIG. 8 illustrates a flowchart of a method for a UE to adjust parametersfor a C-DRX period according to embodiments of the present disclosure;

FIG. 9 illustrates a flowchart of a method for a UE to adjust a numberof PDCCH candidates per CCE aggregation level and per search space setaccording to embodiments of the present disclosure;

FIG. 10 illustrates a flowchart of a method for a UE determination for anumber of PDCell candidates per CCE aggregation level and per searchspace set depending on a corresponding DL BWP according to embodimentsof the present disclosure;

FIG. 11 illustrates a flowchart of a method for a UE to measure andreport CSI for a set of cells according to embodiments of the presentdisclosure;

FIG. 12 illustrates a flowchart of a method for a UE reporting fordetermining a configuration for a number of UE receiver antennasaccording to embodiments of the present disclosure;

FIG. 13 illustrates a flowchart of a method for a UE determination for anumber of UE receiver antennas depending on a corresponding BWPaccording to embodiments of the present disclosure;

FIG. 14 illustrates a flowchart of a method for adaptation of processingtime for scheduling PDSCH/PUSCH reception/transmission on SCell combinedwith an activation or deactivation of the SCell according to embodimentsof the present disclosure;

FIG. 15 illustrates a flowchart of a method for an adaption of slottiming values K1 together with BWP switching and SCellactivation/deactivation according to embodiments of the presentdisclosure; and

FIG. 16 illustrates a call flow for an MCG and an SCG to exchangeinformation to determine respective configurations for communicatingwith a UE according to embodiments of the present disclosure.

DETAILED DESCRIPTION

FIG. 1 through FIG. 16, discussed below, and the various embodimentsused to describe the principles of the present disclosure in this patentdocument are by way of illustration only and should not be construed inany way to limit the scope of the disclosure. Those skilled in the artwill understand that the principles of the present disclosure may beimplemented in any suitably arranged system or device.

The following documents are hereby incorporated by reference into thepresent disclosure as if fully set forth herein: 3GPP TS 38.211 v15.3.0,“NR; Physical channels and modulation;” 3GPP TS 38.212 v15.3.0, “NR;Multiplexing and Channel coding;” 3GPP TS 38.213 v15.3.0, “NR; PhysicalLayer Procedures for Control;” 3GPP TS 38.214 v15.3.0, “NR; PhysicalLayer Procedures for Data;” 3GPP TS 38.321 v15.3.0, “NR; Medium AccessControl (MAC) protocol specification;” and 3GPP TS 38.331 v15.3.0, “NR;Radio Resource Control (RRC) Protocol Specification.”

FIGS. 1-3 below describe various embodiments implemented in wirelesscommunications systems and with the use of orthogonal frequency divisionmultiplexing (OFDM) or orthogonal frequency division multiple access(OFDMA) communication techniques. The descriptions of FIGS. 1-3 are notmeant to imply physical or architectural limitations to the manner inwhich different embodiments may be implemented. Different embodiments ofthe present disclosure may be implemented in any suitably-arrangedcommunications system.

FIG. 1 illustrates an example wireless network according to embodimentsof the present disclosure. The embodiment of the wireless network shownin FIG. 1 is for illustration only. Other embodiments of the wirelessnetwork 100 could be used without departing from the scope of thisdisclosure.

As shown in FIG. 1, the wireless network includes a gNB 101, a gNB 102,and a gNB 103. The gNB 101 communicates with the gNB 102 and the gNB103. The gNB 101 also communicates with at least one network 130, suchas the Internet, a proprietary Internet Protocol (IP) network, or otherdata network.

The gNB 102 provides wireless broadband access to the network 130 for afirst plurality of user equipments (UEs) within a coverage area 120 ofthe gNB 102. The first plurality of UEs includes a UE 111, which may belocated in a small business (SB); a UE 112, which may be located in anenterprise (E); a UE 113, which may be located in a WiFi hotspot (HS); aUE 114, which may be located in a first residence (R); a UE 115, whichmay be located in a second residence (R); and a UE 116, which may be amobile device (M), such as a cell phone, a wireless laptop, a wirelessPDA, or the like. The gNB 103 provides wireless broadband access to thenetwork 130 for a second plurality of UEs within a coverage area 125 ofthe gNB 103. The second plurality of UEs includes the UE 115 and the UE116. In some embodiments, one or more of the gNBs 101-103 maycommunicate with each other and with the UEs 111-116 using 5G, LTE,LTE-A, WiMAX, WiFi, or other wireless communication techniques.

Depending on the network type, the term “base station” or “BS” can referto any component (or collection of components) configured to providewireless access to a network, such as transmit point (TP),transmit-receive point (TRP), an enhanced base station (eNodeB or eNB),a 5G base station (gNB), a macrocell, a femtocell, a WiFi access point(AP), or other wirelessly enabled devices. Base stations may providewireless access in accordance with one or more wireless communicationprotocols, e.g., 5G 3GPP new radio interface/access (NR), long termevolution (LTE), LTE advanced (LTE-A), high speed packet access (HSPA),Wi-Fi 802.11a/b/g/n/ac, etc. For the sake of convenience, the terms “BS”and “TRP” are used interchangeably in this patent document to refer tonetwork infrastructure components that provide wireless access to remoteterminals. Also, depending on the network type, the term “userequipment” or “UE” can refer to any component such as “mobile station,”“subscriber station,” “remote terminal,” “wireless terminal,” “receivepoint,” or “user device.” For the sake of convenience, the terms “userequipment” and “UE” are used in this patent document to refer to remotewireless equipment that wirelessly accesses a BS, whether the UE is amobile device (such as a mobile telephone or smartphone) or is normallyconsidered a stationary device (such as a desktop computer or vendingmachine).

Dotted lines show the approximate extents of the coverage areas 120 and125, which are shown as approximately circular for the purposes ofillustration and explanation only. It should be clearly understood thatthe coverage areas associated with gNBs, such as the coverage areas 120and 125, may have other shapes, including irregular shapes, dependingupon the configuration of the gNBs and variations in the radioenvironment associated with natural and man-made obstructions.

As described in more detail below, one or more of the UEs 111-116include circuitry, programing, or a combination thereof, for receptionreliability for data and control information in an advanced wirelesscommunication system. In certain embodiments, and one or more of thegNBs 101-103 includes circuitry, programing, or a combination thereof,for efficient reduced power consumption in an advanced wirelesscommunication system.

Although FIG. 1 illustrates one example of a wireless network, variouschanges may be made to FIG. 1. For example, the wireless network couldinclude any number of gNBs and any number of UEs in any suitablearrangement. Also, the gNB 101 could communicate directly with anynumber of UEs and provide those UEs with wireless broadband access tothe network 130. Similarly, each gNB 102-103 could communicate directlywith the network 130 and provide UEs with direct wireless broadbandaccess to the network 130. Further, the gNBs 101, 102, and/or 103 couldprovide access to other or additional external networks, such asexternal telephone networks or other types of data networks.

FIG. 2 illustrates an example gNB 102 according to embodiments of thepresent disclosure. The embodiment of the gNB 102 illustrated in FIG. 2is for illustration only, and the gNBs 101 and 103 of FIG. 1 could havethe same or similar configuration. However, gNBs come in a wide varietyof configurations, and FIG. 2 does not limit the scope of thisdisclosure to any particular implementation of a gNB.

As shown in FIG. 2, the gNB 102 includes multiple antennas 205 a-205 n,multiple RF transceivers 210 a-210 n, transmit (TX) processing circuitry215, and receive (RX) processing circuitry 220. The gNB 102 alsoincludes a controller/processor 225, a memory 230, and a backhaul ornetwork interface 235.

The RF transceivers 210 a-210 n receive, from the antennas 205 a-205 n,incoming RF signals, such as signals transmitted by UEs in the network100. The RF transceivers 210 a-210 n down-convert the incoming RFsignals to generate IF or baseband signals. The IF or baseband signalsare sent to the RX processing circuitry 220, which generates processedbaseband signals by filtering, decoding, and/or digitizing the basebandor IF signals. The RX processing circuitry 220 transmits the processedbaseband signals to the controller/processor 225 for further processing.

The TX processing circuitry 215 receives analog or digital data (such asvoice data, web data, e-mail, or interactive video game data) from thecontroller/processor 225. The TX processing circuitry 215 encodes,multiplexes, and/or digitizes the outgoing baseband data to generateprocessed baseband or IF signals. The RF transceivers 210 a-210 nreceive the outgoing processed baseband or IF signals from the TXprocessing circuitry 215 and up-converts the baseband or IF signals toRF signals that are transmitted via the antennas 205 a-205 n.

The controller/processor 225 can include one or more processors or otherprocessing devices that control the overall operation of the gNB 102.For example, the controller/processor 225 could control the reception offorward channel signals and the transmission of reverse channel signalsby the RF transceivers 210 a-210 n, the RX processing circuitry 220, andthe TX processing circuitry 215 in accordance with well-knownprinciples. The controller/processor 225 could support additionalfunctions as well, such as more advanced wireless communicationfunctions. For instance, the controller/processor 225 could support beamforming or directional routing operations in which outgoing signals frommultiple antennas 205 a-205 n are weighted differently to effectivelysteer the outgoing signals in a desired direction. Any of a wide varietyof other functions could be supported in the gNB 102 by thecontroller/processor 225.

The controller/processor 225 is also capable of executing programs andother processes resident in the memory 230, such as an OS. Thecontroller/processor 225 can move data into or out of the memory 230 asrequired by an executing process.

The controller/processor 225 is also coupled to the backhaul or networkinterface 235. The backhaul or network interface 235 allows the gNB 102to communicate with other devices or systems over a backhaul connectionor over a network. The interface 235 could support communications overany suitable wired or wireless connection(s). For example, when the gNB102 is implemented as part of a cellular communication system (such asone supporting 5G, LTE, or LTE-A), the interface 235 could allow the gNB102 to communicate with other gNBs over a wired or wireless backhaulconnection. When the gNB 102 is implemented as an access point, theinterface 235 could allow the gNB 102 to communicate over a wired orwireless local area network or over a wired or wireless connection to alarger network (such as the Internet). The interface 235 includes anysuitable structure supporting communications over a wired or wirelessconnection, such as an Ethernet or RF transceiver.

The memory 230 is coupled to the controller/processor 225. Part of thememory 230 could include a RAM, and another part of the memory 230 couldinclude a Flash memory or other ROM.

Although FIG. 2 illustrates one example of gNB 102, various changes maybe made to FIG. 2. For example, the gNB 102 could include any number ofeach component shown in FIG. 2. As a particular example, an access pointcould include a number of interfaces 235, and the controller/processor225 could support routing functions to route data between differentnetwork addresses. As another particular example, while shown asincluding a single instance of TX processing circuitry 215 and a singleinstance of RX processing circuitry 220, the gNB 102 could includemultiple instances of each (such as one per RF transceiver). Also,various components in FIG. 2 could be combined, further subdivided, oromitted and additional components could be added according to particularneeds.

FIG. 3 illustrates an example UE 116 according to embodiments of thepresent disclosure. The embodiment of the UE 116 illustrated in FIG. 3is for illustration only, and the UEs 111-115 of FIG. 1 could have thesame or similar configuration. However, UEs come in a wide variety ofconfigurations, and FIG. 3 does not limit the scope of this disclosureto any particular implementation of a UE.

As shown in FIG. 3, the UE 116 includes an antenna 305, a radiofrequency (RF) transceiver 310, TX processing circuitry 315, amicrophone 320, and receive (RX) processing circuitry 325. The UE 116also includes a speaker 330, a processor 340, an input/output (I/O)interface (IF) 345, a touchscreen 350, a display 355, and a memory 360.The memory 360 includes an operating system (OS) 361 and one or moreapplications 362.

The RF transceiver 310 receives, from the antenna 305, an incoming RFsignal transmitted by a gNB of the network 100. The RF transceiver 310down-converts the incoming RF signal to generate an intermediatefrequency (IF) or baseband signal. The IF or baseband signal is sent tothe RX processing circuitry 325, which generates a processed basebandsignal by filtering, decoding, and/or digitizing the baseband or IFsignal. The RX processing circuitry 325 transmits the processed basebandsignal to the speaker 330 (such as for voice data) or to the processor340 for further processing (such as for web browsing data).

The TX processing circuitry 315 receives analog or digital voice datafrom the microphone 320 or other outgoing baseband data (such as webdata, e-mail, or interactive video game data) from the processor 340.The TX processing circuitry 315 encodes, multiplexes, and/or digitizesthe outgoing baseband data to generate a processed baseband or IFsignal. The RF transceiver 310 receives the outgoing processed basebandor IF signal from the TX processing circuitry 315 and up-converts thebaseband or IF signal to an RF signal that is transmitted via theantenna 305.

The processor 340 can include one or more processors or other processingdevices and execute the OS 361 stored in the memory 360 in order tocontrol the overall operation of the UE 116. For example, the processor340 could control the reception of forward channel signals and thetransmission of reverse channel signals by the RF transceiver 310, theRX processing circuitry 325, and the TX processing circuitry 315 inaccordance with well-known principles. In some embodiments, theprocessor 340 includes at least one microprocessor or microcontroller.

The processor 340 is also capable of executing other processes andprograms resident in the memory 360, such as processes for beammanagement. The processor 340 can move data into or out of the memory360 as required by an executing process. In some embodiments, theprocessor 340 is configured to execute the applications 362 based on theOS 361 or in response to signals received from gNBs or an operator. Theprocessor 340 is also coupled to the I/O interface 345, which providesthe UE 116 with the ability to connect to other devices, such as laptopcomputers and handheld computers. The I/O interface 345 is thecommunication path between these accessories and the processor 340.

The processor 340 is also coupled to the touchscreen 350 and the display355. The operator of the UE 116 can use the touchscreen 350 to enterdata into the UE 116. The display 355 may be a liquid crystal display,light emitting diode display, or other display capable of rendering textand/or at least limited graphics, such as from web sites.

The memory 360 is coupled to the processor 340. Part of the memory 360could include a random access memory (RAM), and another part of thememory 360 could include a Flash memory or other read-only memory (ROM).

Although FIG. 3 illustrates one example of UE 116, various changes maybe made to FIG. 3. For example, various components in FIG. 3 could becombined, further subdivided, or omitted and additional components couldbe added according to particular needs. As a particular example, theprocessor 340 could be divided into multiple processors, such as one ormore central processing units (CPUs) and one or more graphics processingunits (GPUs). Also, while FIG. 3 illustrates the UE 116 configured as amobile telephone or smartphone, UEs could be configured to operate asother types of mobile or stationary devices.

A communication system includes a downlink (DL) that refers totransmissions from a base station or one or more transmission points toUEs and an uplink (UL) that refers to transmissions from UEs to a basestation or to one or more reception points.

To meet the demand for wireless data traffic having increased sincedeployment of 4G communication systems, efforts have been made todevelop an improved 5G or pre-5G communication system. Therefore, the 5Gor pre-5G communication system is also called a “beyond 4G network” or a“post LTE system.” The 5G communication system is considered to beimplemented in higher frequency (mmWave) bands, e.g., 60 GHz bands, soas to accomplish higher data rates. To decrease propagation loss of theradio waves and increase the transmission distance, the beamforming,massive multiple-input multiple-output (MIMO), full dimensional MIMO(FD-MIMO), array antenna, an analog beam forming, large scale antennatechniques are discussed in 5G communication systems. In addition, in 5Gcommunication systems, development for system network improvement isunder way based on advanced small cells, cloud radio access networks(RANs), ultra-dense networks, device-to-device (D2D) communication,wireless backhaul, moving network, cooperative communication,coordinated multi-points (CoMP), reception-end interference cancellationand the like.

A time unit for DL signaling or for UL signaling on a cell is referredto as a slot and can include one or more symbols. A symbol can alsoserve as an additional time unit. A frequency (or bandwidth (BW)) unitis referred to as a resource block (RB). One RB includes a number ofsub-carriers (SCs). For example, a slot can include 14 symbols, haveduration of 1 millisecond or 0.5 milliseconds, and an RB can have a BWof 180 kHz or 360 kHz and include 12 SCs with inter-SC spacing of 15 kHzor 30 kHz, respectively.

DL signals include data signals conveying information content, controlsignals conveying DL control information (DCI) formats, and referencesignals (RS). A gNB can transmit data information (e.g., transportblocks) or DCI formats through respective physical DL shared channels(PDSCHs) or physical DL control channels (PDCCHs). A gNB can transmitone or more of multiple types of RS including channel state informationRS (CSI-RS) and demodulation RS (DMRS). A CSI-RS is intended for UEs tomeasure channel state information (CSI) or to perform other measurementssuch as ones related to mobility support. A DMRS can be transmitted onlyin a BW of a respective PDCCH or PDSCH and a UE can use the DMRS todemodulate data or control information.

UL signals also include data signals conveying information content,control signals conveying UL control information (UCI), and RS. A UEtransmits data information (e.g., transport blocks) or UCI through arespective physical UL shared channel (PUSCH) or a physical UL controlchannel (PUCCH). When a UE would simultaneously transmit datainformation and UCI, the UE can multiplex both in a PUSCH transmissionor multiplex them separately in respective PUSCH and PUCCHtransmissions. UCI includes hybrid automatic repeat requestacknowledgement (HARQ-ACK) information, indicating correct or incorrectdetection of data transport blocks (TB s) by a UE, scheduling request(SR) indicating whether a UE has data in the UE's buffer, and CSIreports enabling a gNB to select appropriate parameters to perform linkadaptation for PDSCH or PDCCH transmissions to a UE.

A CSI report from a UE can include a channel quality indicator (CQI)informing a gNB of a modulation and coding scheme (MCS) for the UE todetect a data TB with a predetermined block error rate (BLER), such as a10% BLER, of a precoding matrix indicator (PMI) informing a gNB how toprecode signaling to a UE, of a rank indicator (RI) indicating atransmission rank for a PDSCH, of a CSI-RS resource indicator (CRI), andso on. UL RS includes DMRS and sounding RS (SRS). DMRS is transmittedonly in a BW of a respective PUSCH or PUCCH transmission. A gNB can usea DMRS to demodulate information symbols in a respective PUSCH or PUCCH.SRS is transmitted by a UE to provide a gNB with UL CSI and, for a TDDor a flexible duplex system, to also provide a PMI for DL transmissions.An UL DMRS or SRS transmission can be based, for example, on atransmission of a Zadoff-Chu (ZC) sequence or, in general, of a CAZACsequence.

DL transmissions and UL transmissions can be based on an orthogonalfrequency division multiplexing (OFDM) waveform including a variantusing DFT precoding that is known as DFT-spread-OFDM.

FIG. 4 illustrates an example transmitter structure 400 using OFDMaccording to embodiments of the present disclosure. An embodiment of thetransmitter structure 400 shown in FIG. 4 is for illustration only. Oneor more of the components illustrated in FIG. 4 can be implemented inspecialized circuitry configured to perform the noted functions or oneor more of the components can be implemented by one or more processorsexecuting instructions to perform the noted functions. Other embodimentsare used without departing from the scope of the present disclosure.

Information bits, such as DCI bits or data bits 410, are encoded byencoder 420, rate matched to assigned time/frequency resources by ratematcher 430 and modulated by modulator 440. Subsequently, modulatedencoded symbols and DMRS or CSI-RS 450 are mapped to SCs 460 by SCmapping unit 465, an inverse fast Fourier transform (IFFT) is performedby filter 470, a cyclic prefix (CP) is added by CP insertion unit 480,and a resulting signal is filtered by filter 490 and transmitted by anradio frequency (RF) unit 495.

FIG. 5 illustrates an example receiver structure 500 using OFDMaccording to embodiments of the present disclosure. An embodiment of thereceiver structure 500 shown in FIG. 5 is for illustration only. One ormore of the components illustrated in FIG. 8 can be implemented inspecialized circuitry configured to perform the noted functions or oneor more of the components can be implemented by one or more processorsexecuting instructions to perform the noted functions. Other embodimentsare used without departing from the scope of the present disclosure.

A received signal 510 is filtered by filter 520, a CP removal unitremoves a CP 530, a filter 540 applies a fast Fourier transform (FFT),SCs de-mapping unit 550 de-maps SCs selected by BW selector unit 555,received symbols are demodulated by a channel estimator and ademodulator unit 560, a rate de-matcher 570 restores a rate matching,and a decoder 580 decodes the resulting bits to provide information bits590.

A UE typically monitors multiple candidate locations for respectivepotential PDCCH receptions (PDCCH candidates) to decode respectivecandidate DCI formats in a slot. The locations are determined accordingto a search space for a respective DCI format. Monitoring PDCCHcandidates means receiving and decoding the PDCCH candidates accordingto DCI formats the UE is configured to receive. A DCI format includescyclic redundancy check (CRC) bits in order for the UE to confirm acorrect detection of the DCI format. A DCI format type is identified bya radio network temporary identifier (RNTI) that scrambles the CRC bits.For a DCI format scheduling a PDSCH or a PUSCH to a single UE, the RNTIcan be a cell RNTI (C-RNTI) and serves as a UE identifier.

For example, for a DCI format scheduling a PDSCH conveying systeminformation (SI), the RNTI can be an SI-RNTI. For a DCI formatscheduling a PDSCH providing a random-access response (RAR), the RNTIcan be an RA-RNTI. For a DCI format scheduling a PDSCH providing paginginformation, the RNTI can be a P-RNTI. For a DCI format scheduling aPDSCH or a PUSCH to a single UE prior to UE establishing a radioresource control (RRC) connection with a serving gNB, the RNTI can be atemporary C-RNTI (TC-RNTI). For a DCI format providing TPC commands to agroup of UEs, the RNTI can be a TPC-PUSCH-RNTI or a TPC-PUCCH-RNTI. EachRNTI type can be configured to a UE through higher-layer signaling suchas RRC signaling. A DCI format scheduling PDSCH reception to a UE isalso referred to as DL DCI format or DL assignment while a DCI formatscheduling PUSCH transmission from a UE is also referred to as UL DCIformat or UL grant.

A PDCCH transmission can be within a set of physical RBs (PRBs). A gNBcan configure a UE one or more sets of PRBs, also referred to as controlresource sets (CORESETs), for PDCCH receptions. A PDCCH reception can bein control channel elements (CCEs) that are included in a controlresource set. A UE determines CCEs for a PDCCH reception based on asearch space such as a UE-specific search space (USS) for PDCCHcandidates associated with DCI formats having CRC scrambled by a RNTI,such as a C-RNTI, that is configured to the UE by UE-specific RRCsignaling for scheduling unicast PDSCH reception or PUSCH transmission,and a common search space (CSS) for PDCCH candidates associated with DCIformats having CRC scrambled by other RNTIs. A set of CCEs that can beused for PDCCH transmission to a UE define a PDCCH candidate location. Aproperty of a control resource set is transmission configurationindication (TCI) state that provides quasi co-location information ofthe DMRS antenna port for PDCCH reception.

FIG. 6 illustrates an example encoding process 600 for a DCI formataccording to embodiments of the present disclosure. An embodiment of theencoding process 600 shown in FIG. 6 is for illustration only. One ormore of the components illustrated in FIG. 6 can be implemented inspecialized circuitry configured to perform the noted functions or oneor more of the components can be implemented by one or more processorsexecuting instructions to perform the noted functions. Other embodimentsare used without departing from the scope of the present disclosure.

A gNB separately encodes and transmits each DCI format in a respectivePDCCH. A RNTI masks a CRC of the DCI format codeword in order to enablethe UE to identify the DCI format. For example, the CRC and the RNTI caninclude, for example, 16 bits or 24 bits. The CRC of (non-coded) DCIformat bits 610 is determined using a CRC computation unit 620, and theCRC is masked using an exclusive OR (XOR) operation unit 630 between CRCbits and RNTI bits 640. The XOR operation is defined as XOR(0,0)=0,XOR(0,1)=1, XOR(1,0)=1, XOR(1,1)=0. The masked CRC bits are appended toDCI format information bits using a CRC append unit 650. An encoder 660performs channel coding (such as tail-biting convolutional coding orpolar coding), followed by rate matching to allocated resources by ratematcher 670. Interleaving and modulation units 680 apply interleavingand modulation, such as QPSK, and the output control signal 690 istransmitted.

FIG. 7 illustrates an example decoding process 700 for a DCI format foruse with a UE according to embodiments of the present disclosure. Anembodiment of the decoding process 700 shown in FIG. 7 is forillustration only. One or more of the components illustrated in FIG. 7can be implemented in specialized circuitry configured to perform thenoted functions or one or more of the components can be implemented byone or more processors executing instructions to perform the notedfunctions. Other embodiments are used without departing from the scopeof the present disclosure.

A received control signal 710 is demodulated and de-interleaved by ademodulator and a de-interleaver 720. A rate matching applied at a gNBtransmitter is restored by rate matcher 730, and resulting bits aredecoded by decoder 740. After decoding, a CRC extractor 750 extracts CRCbits and provides DCI format information bits 760. The DCI formatinformation bits are de-masked 770 by an XOR operation with an RNTI 780(when applicable) and a CRC check is performed by unit 790. When the CRCcheck succeeds (check-sum is zero), the DCI format information bits areconsidered to be valid. When the CRC check does not succeed, the DCIformat information bits are considered to be invalid.

For each DL bandwidth part (BWP) configured to a UE in a serving cell, aUE can be provided by higher layer signaling a number of controlresource sets. For each control resource set, the UE is provided: acontrol resource set index p; a demodulation reference-signal (DM-RS)scrambling sequence initialization value; a precoder granularity for anumber of REGs in frequency where the UE can assume use of a same DM-RSprecoder; a number of consecutive symbols; a set of resource blocks;CCE-to-REG mapping parameters; an antenna port quasi co-location, from aset of antenna port quasi co-locations, indicating quasi co-locationinformation of the DM-RS antenna port for PDCCH reception; and anindication for a presence or absence of a transmission configurationindication (TCI) field for a DCI format 1_1 multiplexed in a PDCCHreception in control resource set p.

For each DL BWP configured to a UE in a serving cell, the UE is providedby higher layers with a number of search space sets where, for eachsearch space set from the number search space sets, the UE is providedthe following: a search space set index s; an association between thesearch space set s and a control resource set p; a PDCCH monitoringperiodicity of k_(p,s), slots and a PDCCH monitoring offset of o_(p,s)slots; a PDCCH monitoring pattern within a slot, indicating firstsymbol(s) of the control resource set within a slot for PDCCHmonitoring; a number of PDCCH candidates M_(p,s) ^((L)) per CCEaggregation level L; and an indication that search space set s is eithera common search space set or a UE-specific search space set.

For a search space set s associated with control resource set p, the CCEindexes for aggregation level L corresponding to PDCCH candidate m_(s,n)_(CI) of the search space set in slot n_(s,f) ^(μ) for a serving cellcorresponding to carrier indicator field value n_(CI) (also referred toas search space) are given as in Equation 1:

$\begin{matrix}{{L \cdot \left\{ {\left( {Y_{p,n_{s,f}^{\mu}} + \left\lfloor \frac{m_{s,n_{CI}} \cdot N_{{CCE},p}}{L \cdot M_{p,s,\max}^{(L)}} \right\rfloor + n_{CI}} \right){mod}\left\lfloor \frac{N_{{CCE},p}}{L} \right\rfloor} \right\}} + i} & {{Equation}\mspace{14mu} 1}\end{matrix}$

In Equation 1, for any common search space, Y_(p,n) _(s,f) _(μ) =0; fora UE-specific search space, Y_(p,n) _(s,f) _(μ) =(A_(p)·Y_(p,n) _(s,f)_(μ) ⁻¹) mod D, Y_(p,−1)=n_(RNTI)≠0, A₀=39827 for p mod 3=0, A₁=39829for p mod 3=1, A₂=39839 for p mod 3=2, and D=65537; i=0, . . . , L−1;N_(CCE,p) is the number of CCEs, numbered from 0 to N_(CCE,p)−1, incontrol resource set p; n_(CI) is the carrier indicator field value ifthe UE is configured with a carrier indicator field; otherwise,including for any common search space, n_(CI)=0; m_(s,n) _(CI) =0, . . ., M_(s,n) _(CI) ^((L))−1, where M_(p,s,n) _(CI) ^((L)) is the number ofPDCCH candidates the UE is configured to monitor for aggregation level Lfor a serving cell corresponding to n_(CI) and a search space set s; forany common search space, M_(p,s,max) ^((L))=M_(p,s,0) ^((L)); for aUE-specific search space M_(p,s,max) ^((L)) is the maximum of M_(p,s,n)_(CI) ^((L)) across all configured n_(CI) values for a CCE aggregationlevel L of search space set s in control resource set p; and the RNTIvalue used for n_(RNTI).

When a UE indicates a carrier aggregation capability larger than 4serving cells, the UE indicates a number of DL cells N_(cells) ^(cap)that the UE can monitor a maximum number of PDCCH candidates andnon-overlapping CCEs per slot when the UE is configured for carrieraggregation operation over more than 4 cells.

When a UE is configured with N_(cells) ^(DL,μ) downlink cells with DLBWPs having SCS configuration μ where Σ_(μ=0) ³ N_(cells)^(DL,μ)≤N_(cells) ^(cap), the UE is not required to monitor, on theactive DL BWP of the scheduling cell, more than M_(PDCCH)^(total,slot,μ)=M_(PDCCH) ^(max,slot,μ) PDCCH candidates or more thanC_(PDCCH) ^(total,slot,μ)=C_(PDCCH) ^(max,slot,μ) non-overlapped CCEsper slot for each scheduled cell where M_(PDCCH) ^(max,slot,μ) andC_(PDCCH) ^(max,slot,μ) are respectively a maximum number of PDCCHcandidates and a maximum number of non-overlapping CCEs that a UE canmonitor/process per slot for SCS configuration μ.

When a UE is configured with N_(cells) ^(DL, μ) downlink cells with DLBWPs having SCS configuration μ, where Σ_(μ=0) ³N_(cells)^(DL,μ)>N_(cells) ^(cap), a DL BWP of an activated cell is the active DLBWP of the activated cell, and a DL BWP of a deactivated cell is the DLBWP with index provided by higher layers for the deactivated cell, theUE is not required to monitor more than M_(PDCCH)^(total,slot,μ)=└N_(cells) ^(cap)·M_(PDCCH) ^(max,slot,μ)·N_(cells)^(DL,μ)/Σ_(j=0) ³N_(cells) ^(DL,j)┘ PDCCH candidates or more thanC_(PDCCH) ^(total,slot,μ)=└N_(cells) ^(cap)·C_(PDCCH)^(max,slot,μ)·N_(cells) ^(DL,μ)/Σ_(j=0) ³N_(cells) ^(DL,j)┘non-overlapped CCEs per slot on the active DL BWP(s) of schedulingcell(s) from the N_(cells) ^(DL,μ) downlink cells. M_(PDCCH)^(total,slot,μ)=└N_(cells) ^(cap)·M_(PDCCH) ^(max,slot,μ)/Σ_(j=0)³N_(cells) ^(DL,j)┘=└N_(cells) ^(cap)·M_(PDCCH) ^(max,slot,μ)/N_(cells)^(DL,j)┘.

A PUCCH can be transmitted according to one from multiple PUCCH formats.A PUCCH format corresponds to a structure that is designed for aparticular UCI payload range as different UCI payloads require differentPUCCH transmission structures to improve an associated UCI BLER. A PUCCHtransmission is also associated with a transmission configurationindicator (TCI) state providing a spatial domain filter for a PUCCHtransmission. A PUCCH can be used to convey HARQ-ACK information, SR, orperiodic/semi-persistent CSI and their combinations.

A UE can be configured for operation with multiple bandwidth parts (BWP)in a DL system BW (DL BWPs) or in an UL system BW (UL BWPs). At a giventime, only one DL BWP and only one UL BWP are active for the UE.Therefore, DL receptions are on the active DL BWP and UL transmissionsare on the active UL BWP. It is also possible for more than one DL BWPsor UL BWPs to be active at a same time and then more than one DLreceptions or UL transmissions can simultaneously occur in the more thanone DL BWPs or UL BWPs, respectively. Configurations of variousparameters, such as search space sets configuration for PDCCH receptionor PUCCH resources for PUCCH transmission, can be separately providedfor each respective BWP.

A primary purpose for BWP operation is to enable power savings for a UE.When the UE has data to transmit or receive, a large BWP can be usedand, for example, more than one search space sets can be configured withshort monitoring periodicities. When the UE does not have data totransmit or receive, a small BWP can be used and, for example, a singlesearch space set can be configured with longer monitoring periodicity.

Another mechanism for UE power savings can be an operation withdiscontinuous reception (e.g., C-DRX operation) when a UE has an RRCconnection with a serving gNB (e.g., RRC_CONNECTED mode). When a UE isin RRC_CONNECTED mode, the UE operates in C-DRX mode that is associatedwith parameters “on duration” and “inactivity timer”. During the “onduration” period, the UE monitors PDCCH (attempts to detect DCI formats)in configured search space sets. When the UE detects a DCI formatscheduling a PDSCH reception or a PUSCH transmission during the “onduration” period, the UE starts the “inactivity timer” and continues tomonitor PDCCH until the “inactivity timer” expires and the UE goes intosleep mode for power saving.

A configuration for values of the “on duration” and “inactivity timer”is determined by a serving gNB and there is no UE feedback for preferredvalues. For example, based on a power level or on the power consumptionfor a specific carrier or BWP, the UE can suggest values for the “onduration” and “inactivity timer”. For example, a UE with low batterypower can suggest a larger value for the “on duration” period and asmaller value for the “inactivity timer”.

Most of the UE modem power is often consumed, depending on the datatraffic application, on monitoring PDCCH while in many C-DRX periods theUE does not detect any DCI format and, even in C-DRX periods where theUE detects a DCI format, the inactivity timer expires without the UEdetecting another DCI format. For this reason, use of “wake-upsignalling” (WUS) or “go-to-sleep” (GTS) signalling have been consideredin order to respectively indicate to a UE to wake-up and startmonitoring PDCCH, instead of the UE doing so automatically at the startof each C-DRX period, or to stop monitoring PDCCH until the start of thenext C-DRX period or until the UE detects a corresponding WUS.

For certain frequency bands, it is mandatory for a UE to supportoperation with 4 receiver antennas. Such a large number of receiverantennas results to large UE power consumption and may not be necessaryor preferable when the UE is to receive small data packets, or when theUE is in good coverage, or when the UE has low battery power. Arecommendation by the UE for a preferred number of receiver antennas,either directly or indirectly, can also facilitate reduced UE powerconsumption.

Similar to adapting a number of UE receiver antennas, a number ofactivated secondary cells (SCells) for a UE can be adapted according toa buffer status for the UE. Existing networks supportactivation/deactivation of SCells by MAC layer signaling but this oftenrequires material delays particularly for CSI measurements and feedbackafter a SCell is activated and, due to this reason, this feature isoften not used by a serving gNB as there is no incentive for the gNB todeactivate (and subsequently activate) SCells. Instead, a serving gNBtypically maintains a configured SCell for a UE in the activated stateeven when there is no data in the buffer for transmission to the UE.

Cross-slot scheduling of PDSCH receptions or PUSCH transmissions is alsoconsidered to enable UE power savings. A UE can perform light sleep fora period indicated by the delay between scheduling PDCCH and thescheduled PDSCH/PUSCH reception/transmission, denoted as K0/K2,respectively. However, a power saving period is constrained by the startof a next PDCCH monitoring occasion. The UE may switch from a lightsleep mode to a regular active mode as long as the next PDCCH monitoringoccasion starts, regardless of whether or not the timer associated withcurrent K0/K2 expires.

NR supports semi-static (Type-1) and dynamic (Type-2) HARQ-ACK codebookdetermination where a UE provides HARQ-ACK information for a set ofPDSCH reception occasions in one PUCCH or PUSCH transmission. Thisenables the UE to save power by reducing a number of PUCCH transmissionsto provide HARQ-ACK information and, for unpaired spectrum operation,reducing an overhead for switching between receptions in a DL andtransmissions in an UL. For a semi-static HARQ-ACK codebook, the UEdetermines a HARQ-ACK codebook size by a set of slot timing values K1for PUCCH transmissions with HARQ-ACK information. The UE can beprovided the set of slot timing values K1 by a higher layer parameter,such as dl_DataTo_UL_ACK, for a DCI format 1_1.

For example, a set of slot timing values K1 can include 8 elements withvalues ranging from 0 to 15 or 31. However, a semi-static configurationof slot timing values may not be efficient in adapting to different datatraffic loads. Also, UE power saving gains are not balanced fordifferent numerologies. For example, with a same configuration for slottiming values, a UE operating in frequency range 2 (FR2—for carrierfrequencies above 6 GHz) requires more power consumption than a UEoperating in frequency range 1 (FR1—for carrier frequencies below 6GHz). This is due to more frequent transmissions of HARQ-ACK informationand, for unpaired spectrum operation such as in FR2, due to an increasedoverhead for DL to UL switching.

To reduce a number of non-overlapping CCEs that PDCCH candidates occupy,as determined according to a search space determination as in Equation1, a nested search space can be used. For example, with a nested searchspace, a search space can be determined according to Equation 1 forpredetermined PDCCH candidates and a search space for remaining PDCCHcandidates can include only the CCEs of the predetermined PDCCHcandidates using either Equation 1 or some other structure.

For example, the predetermined PDCCH candidates can be the (non-zero)PDCCH candidates with the largest CCE aggregation level. For example,the predetermined PDCCH candidates can be the ones requiring the largestnumber of CCEs where, for example 4 PDCCH candidates with aggregationlevel of 4 CCEs require 16 CCEs that are more than the 8 CCEs requiredby 1 PDCCH candidate with aggregation level of 1 CCE.

A tradeoff between a nested search space and a search space according toEquation 1 is that the former reduces a number of non-overlapping CCEswhile the latter reduces a blocking probability for PDCCH transmissions.Therefore, there is a need to enable a gNB to adapt a search spaceselection for a UE according to whether the gNB prioritizes the formeror the latter part of the tradeoff for the UE and to even enable the gNBto apply both parts of the tradeoff.

Therefore, there is a need to indicate to a UE whether or not to monitorPDCCH candidates for a number of C-DRX periods or for a number of PDCCHmonitoring occasions within a C-DRX period.

There is another need to provide means to a UE to indicate to a servinggNB preferred configurations for transmissions and receptions.

There is another need to enable a UE to perform fast SCell activationand deactivation.

There is another need to design new operating modes for communicationbetween a UE and a serving gNB that enable UE power savings withoutpenalizing network operation.

There is another need to adapt a set of slot timing values K1 for bothsemi-static and dynamic HARQ-ACK codebook determination with respect toa number of active SCells and a corresponding subcarrier spacingconfiguration.

There is another need for a MN, a SN, and a UE to have a sameunderstanding for a number of PDCCH candidates the UE is expected tomonitor per slot and for a number of non-overlapping CCEs the UE isexpected to be able to perform channel estimation per slot.

Finally, there is a need to set a processing time for schedulingPDSCH/PUSCH and to combine an activation/deactivation of secondarycarriers together with dynamic adaptation on processing time forscheduling.

The present disclosure relates to a pre-5^(th)-generation (5G) or 5Gcommunication system to be provided for supporting higher data ratesbeyond 4^(th)-generation (4G) communication system such as long termevolution (LTE). The present disclosure relates to indicating to a UEwhether or not to monitor PDCCH candidates for a C-DRX period or for aPDCCH monitoring occasion within a C-DRX period. The present disclosurealso relates to providing means to a UE to indicate to a serving gNBpreferred configurations for transmissions and receptions. The presentdisclosure further relates to enabling a UE to perform fast SCellactivation and deactivation. The present disclosure additionally relatesto designing new operating modes for communication between a UE and aserving gNB that enable UE power savings without penalizing networkoperation.

The present disclosure also relates to adapting a set of slot timingvalue K1 for both semi-static and dynamic HARQ-ACK codebookdetermination with respect to a number of active SCells and acorresponding subcarrier spacing configuration. The present disclosurefurther relates to establishing a same understanding among a MN, a SN,and a UE for a number of PDCCH candidates the UE is expected to monitorper slot and for a number of non-overlapping CCEs the UE is expected tobe able to perform channel estimation per slot. The present disclosureadditionally relates to setting a processing time for schedulingPDSCH/PUSCH and to combining an activation/deactivation of secondarycarriers together with dynamic adaptation on processing time forscheduling.

In one embodiment, signaling designs are provided for indicating to a UEto skip PDCCH monitoring for a number of C-DRX cycles, or to skip PDCCHmonitoring within a C-DRX cycle, or to adjust parameters for a number ofC-DRX cycles.

An indication for an adjustment to a number of configured PDCCHcandidates that a UE monitors in a search space set can be provided by aDCI format. A DCI format can be decoded by multiple UEs (UE-common DCIformat) in a PDCCH received in a common search space or can beUE-specific in a PDCCH received in a UE-specific search space.Enhancements to the structure of a DCI format and of the contents forthe information it provides with respect to PDCCH monitoring by a UE arenow described.

In case of a UE-common DCI format, a UE is configured with a RNTI,referred to for example as PS-RNTI, for a DCI format and with a locationfor a field that includes a number of consecutive bits in a DCI format.The UE can be configured one location/field corresponding to one cell orto a group of cells that can be for example indicated by higher layersor can be configured multiple locations/fields corresponding torespective multiple cells or multiple groups of cells. For brevity, aDCI format is referred to as a DCI format P.

For indication of PDCCH monitoring per C-DRX period to a UE, the UEmonitors PDCCH for a DCI format P only at the beginning of a C-DRXperiod or at one or more times/occasions provided by higher layers priorto the beginning of a C-DRX period, such as for example 1 msec prior tothe beginning of a C-DRX period, in order to provide to the UEsufficient processing time to apply the indications by a DCI format P atthe beginning of the C-DRX period and to potentially perform CSI-RSmeasurements and provide a CSI report prior to the beginning of theC-DRX period.

A number of PDCCH candidates per CCE aggregation level for a PDCCHreception for a DCI format P can be configured to a UE or, to reduce anumber of decoding operations, expedite decoding of a DCI format P, andminimize associated UE power consumption, only one or two CCEaggregation levels can be configured to the UE for monitoring PDCCH witha DCI format P and a number of PDCCH candidates for the CCE aggregationlevel can be also configured, up to a predetermined maximum number suchas 2 or 4, or can be defined in a system operation. The one or two CCEaggregation levels for a PDCCH that includes the DCI format P can alsobe defined in the system operation.

A number of bits in the field (either in a UE-specific DCI format or ina UE-common DCI format) can be one or more. In case of one bit, theindication can be whether or not the UE skips PDCCH monitoring in thenext C-DRX period or in a number of C-DRX periods that the UE isprovided in advance by higher layer signaling. For example, a value of“0” can indicate skipping of PDCCH monitoring while a value of “1” canindicate PDCCH monitoring in the next C-DRX period.

In case of multiple bits, in one embodiment, the indication can includeadjustments to the parameters of the C-DRX period by indicating valuesfor the “on duration” parameter and the “inactivity timer” parameterfrom a set of corresponding values that the UE is provided in advance byhigher layers. The indication can also include adjustments to a numberof PDCCH candidates a UE is configured to monitor in order to detect DCIformats scheduling PDSCH receptions or PUSCH transmissions.

For example, in case of 2 bits, a “00” value can indicate to a UE toskip PDCCH monitoring in a next C-DRX period while a “01,” “10” or “11”value can respectively indicate a first, second, or third set of “onduration, inactivity timer” values where the three sets of “on duration,inactivity timer” values were provided in advance to the UE by higherlayers.

In another embodiment, the indication can be a number of slots in aC-DRX period, from a set of numbers of slots that the UE is provided inadvance by higher layer signaling or are defined in a system operation,that the UE skips PDCCH monitoring. For example, in case of 2 bits, a“00” value can indicate to a UE to monitor PDCCH in every slot of aC-DRX period (i.e., not skip PDCCH monitoring) while a “01,” “10” or“11” value can respectively indicate to a UE to skip PDCCH monitoringfor N1, N2, or N3 slots where the values of N1, N2, and N3 are providedto the UE by higher layers.

For example, for a DCI format P reception periodicity of N slots and incase of 2 bits, a “00” value can indicate to a UE to monitor PDCCH inevery slot of a C-DRX period (i.e., not skip PDCCH monitoring) while a“01” “10,” or “11” value can respectively indicate to a UE to skip PDCCHmonitoring in every fourth slot of the next N slots (either including orexcluding the slot of the DCI format P reception), in every second slotof the next N slots, or in all next N slots, where N can be provided tothe UE by higher layers or can include all remaining slots in the C-DRXperiod. For PDCCH monitoring occasions where the UE skips PDCCHmonitoring, the UE still increments the Inactivity Timer.

The UE can also be configured by higher layers a periodicity for a DCIformat P reception and the UE applies a corresponding configuration fora set “on duration, inactivity timer” values for all C-DRX periods untila C-DRX period that corresponds to a next DCI format P reception. Whenthe UE fails to detect a DCI format P at a corresponding monitoringoccasion, the UE assumes maximum values, from the configured values, forthe on duration and for the inactivity timer. This ensures that thePDCCH monitoring occasions are a superset of the ones indicated by a DCIformat P and the UE does not miss reception of a PDCCH transmission fromthe gNB.

Alternatively, the UE can assume a predetermined set of values from theconfigured sets of values, such as the first set of “on duration,inactivity timer” values and it can be up to gNB implementation toensure appropriate values, such as maximum values, in case a UE fails todetect a DCI format P. In case of cross-carrier scheduling, a same setof “on duration, inactivity timer” values can apply for each searchspace set corresponding to each scheduled cell with a same schedulingcell.

FIG. 8 illustrates a flowchart of a method 800 for a UE to adjustparameters for a C-DRX period according to embodiments of the presentdisclosure. An embodiment of the method 800 shown in FIG. 8 is forillustration only. One or more of the components illustrated in FIG. 8can be implemented in specialized circuitry configured to perform thenoted functions or one or more of the components can be implemented byone or more processors executing instructions to perform the notedfunctions. Other embodiments are used without departing from the scopeof the present disclosure.

Using higher layer signaling, a gNB configures a UE with a RNTI for aDCI format P, a periodicity for a DCI format P reception, one or moreoffsets for PDCCH monitoring prior to a start of a DRX-cycle for DCIformat P, and with a location of a field in the DCI format P thatindicates a configuration for a set of values for “on duration” and“inactivity timer” parameters for C-DRX periods until a next receptionof DCI format P in step 810. The UE determines whether or not the UEdetects the DCI format P at a configured reception time in step 820.When the UE does not detect the DCI format P, the UE assumes maximumvalues, from the respective configured values, for a set of “onduration, inactivity timer” values in step 830. When the UE detects theDCI format P, the UE monitors PDCCH in a C-DRX period according to a setof “on duration, inactivity timer” values indicated by a correspondingfield for the UE in the DCI format P in step 840. When the fieldindicates a predetermined value, such as “00,” the UE can skip PDCCHdecoding for all C-DRX periods until a next monitoring occasion for theDCI format P.

Each set of “on duration, inactivity timer” values can be configured tobe associated with a set of search space sets that the UE is configuredin advance by higher layers. For example, a UE can be configured tomonitor up to four search space sets in a C-DRX period for PDCCHreceptions conveying UE-specific DCI formats and a first, second, andthird set of “on duration, inactivity timer” values can be respectivelyassociated by higher layer signaling with a first, second, and thirdsubsets of the set of the search space sets.

For example the first set of “on duration, inactivity timer” values canbe associated with the first two search space sets (in the order ofconfiguration), the second set of “on duration, inactivity timer” valuescan be associated with the first three search space sets, and the thirdset of “on duration, inactivity timer” values can be associated with allfour search space sets.

Each set of “on duration, inactivity timer” values can be configured tobe associated with a percentage (or fraction) of PDCCH candidates thatthe UE is configured in advance by higher layers. For example, a UE canbe configured to monitor PDCCH candidates for scheduling of PDSCHreceptions or PUSCH transmissions in a number of search space sets in aC-DRX period. A first, second, and third set of “on duration, inactivitytimer” values can be respectively associated by higher layer signalingwith a first, second, and third percentages for a number of PDCCHcandidates per CCE aggregation level per search space set, where thefloor function or the ceiling function can apply if a percentage doesnot result to an integer number of PDCCH candidates for a respective CCEaggregation level in a search space set.

For example the first set of “on duration, inactivity timer” values canbe associated with all the PDCCH candidates per CCE aggregation level ineach search space set, the second set of “on duration, inactivity timer”values can be associated with ⅔ of the PDCCH candidates per CCEaggregation level in each search space set, and the third set of “onduration, inactivity Timer” values can be associated with ⅓ of the PDCCHcandidates per CCE aggregation level in each search space set.

The fractions can also be configured by higher layers instead of beingpredetermined as in the previous example with the possible exception ofthe first value that can always be one. As an alternative, instead ofthe first, second, and third sets of “on duration, inactivity timer”values to be associated with respective first, second, and thirdfractions of PDCCH candidates per CCE aggregation level per search spaceset, three separate configurations for PDCCH candidates per CCEaggregation level per search space set can be provided and can beassociated with the three corresponding sets of “on duration, inactivitytimer” values.

When a UE fails to detect a DCI format P at a corresponding PDCCHmonitoring occasion, the UE monitors PDCCH for a corresponding C-DRXperiod according to default settings such as for example according to afirst configuration, such as the configuration with the maximum numberof candidates per CCE aggregation level and per search space set (or theconfiguration corresponding to a fraction value of 1), for a number ofPDCCH candidates per CCE aggregation level for a respective search spaceset.

FIG. 9 illustrates a flowchart of a method 900 for a UE to adjust anumber of PDCCH candidates per CCE aggregation level and per searchspace set according to embodiments of the present disclosure. Anembodiment of the method 900 shown in FIG. 9 is for illustration only.One or more of the components illustrated in FIG. 9 can be implementedin specialized circuitry configured to perform the noted functions orone or more of the components can be implemented by one or moreprocessors executing instructions to perform the noted functions. Otherembodiments are used without departing from the scope of the presentdisclosure.

Using higher layer signaling, a gNB configures a UE an associationbetween each set of “on duration, inactivity timer” values and afraction of PDCCH candidates, relative to a configured number of PDCCHcandidates, per CCE aggregation level for each search space set in step910.

The UE determines whether or not the UE detects a DCI format P at aconfigured reception time in step 920. When the UE does not detect a DCIformat P, the UE assumes the configured number of PDCCH candidates perCCE aggregation level for each search space set in step 930. When the UEdetects a DCI format P, the UE determines a set of “on duration,inactivity timer” values, for example as described in FIG. 8, and basedon a corresponding association with a fraction of PDCCH candidates, theUE determines a number of PDCCH candidates per CCE aggregation level foreach search space set in step 940.

In order to minimize an overhead associated with a DCI format P or toincrease a number of UEs that the DCI format P can address or an amountof information that a DCI format P can provide, a CRC length for a DCIformat P can be smaller than a CRC length for other DCI formats such asDCI formats scheduling PDSCH receptions or PUSCH transmissions.

For example, a CRC length for a DCI format P can be 8 bits or 16 bitswhile a CRC length for the other DCI formats can be 24 bits. When aserving gNB does not transmit a DCI format P but a UE incorrectlydetects a DCI format P due to a false CRC check, the worst outcome isthat a UE may not monitor PDCCH for a C-DRX period where the serving gNBexpects the UE to monitor PDCCH but it is possible for the gNB torealize this through DTX detection of a PUCCH conveying correspondingHARQ-ACK information if the gNB schedules PDSCH receptions to the UE orthrough DTX detection of a PUSCH reception if the gNB schedules PUSCHtransmissions to the UE.

When a UE is configured for operation with carrier aggregation, the UEcan be configured a number of fields in a DCI format P equal to acorresponding number of cells or groups of cells and the previouslydescribed functionality of a DCI format P for single cell operation canbe parallelized for the corresponding number of fields to a number ofcells or groups of cells in the operation with carrier aggregation. Thecells in a group of cells can be configured in advance by higher layersor be implicitly determined by the cell index and a number of cells in agroup of cells.

An adaptation of set of “on duration, inactivity timer” values for aC-DRX cycle can also depend on a DL BWP used for receptions by a UE. Forexample, a configuration for a set of “on duration, inactivity timer”values can be independently provided for each BWP, or for a first BWPand remaining BWPs.

For example, smaller values for the “on duration” and for the“inactivity timer” can be configured in a first DL BWP that is used whenthe gNB does not have a large amount of data in the gNB's buffer for theUE and high data rates are not required and larger values for the “onduration” and for the “inactivity timer” can be configured in a secondDL BWP that is used when the gNB wants to achieve high data rates forthe UE.

FIG. 10 illustrates a flowchart of a method 1000 for a UE determinationfor a number of PDCCH candidates per CCE aggregation level and persearch space set depending on a corresponding DL BWP according toembodiments of the present disclosure. An embodiment of the method 1000shown in FIG. 10 is for illustration only. One or more of the componentsillustrated in FIG. 10 can be implemented in specialized circuitryconfigured to perform the noted functions or one or more of thecomponents can be implemented by one or more processors executinginstructions to perform the noted functions. Other embodiments are usedwithout departing from the scope of the present disclosure.

A gNB configures, using higher layer signaling, a first value for an “onduration” and a first value for an “inactivity timer” associated with aC-DRX period in a first DL BWP and a second value for an “on duration”and a second value for an “inactivity timer” associated with a C-DRXperiod in a second DL BWP in step 1010. The UE determines whether anactivated DL BWP is the first DL BWP or the second DL BWP in step 1020.When the activated DL BWP is the first DL BWP, the UE uses the firstvalues for the “on duration” and the “inactivity timer” parameters for aC-DRX period in step 1030. When the activated DL BWP is the second DLBWP, the UE uses the second values for the “on duration” and the“inactivity timer” parameters for a C-DRX period in step 1040.

An indication by a DCI format P (that can be either UE-common orUE-specific such as a DCI format 0_1 or a DCI format 1_1) may not applyin slots or in PDCCH monitoring occasions where a UE also monitors PDCCHin a common search space since the UE needs to anyway have the UE'sradio-frequency active and decode at least one DCI format. This can befurther restricted to the common search space corresponding to DCIformats scheduling a PDSCH receptions, such as DCI formats with CRCscrambled by an SI-RNTI, or an RA-RNTI, or a P-RNTI, as for DCI formatsthat do not schedule PDSCH reception, such as a DCI format with CRCscrambled by a TPC-PUSCH-RNTI, TPC-PUCCH-RNTI, or a SFI-RNTI, the UE canstill save power as the UE does not need to be prepared to receive aPDSCH. Therefore, a UE can decode UE-specific DCI formats at least inPDCCH monitoring occasions or slots where the UE decodes a UE-common DCIformat that schedules a PDSCH reception.

Dynamic Activation of Secondary Cells

A primary source of delay for an activation of a secondary cell isassociated with a delay for a UE to provide a CSI feedback to a servinggNB for the secondary cell. Further, the CSI feedback may indicate achannel quality that is not sufficiently good for the gNB to schedulePDSCH transmissions to the UE in the secondary cell. Additional latencyis then required for the gNB to activate another set of secondary cellsfor the UE, obtain corresponding CSI feedback, and deactivate cells thatare not associated with sufficiently good CSI feedback.

To avoid this delay shortcoming in activating secondary cells, LTEoperations introduced a new SCell state, so-called dormant state, wherea UE can measure and report periodic CSI feedback for the SCell whilethe new SCell state is otherwise same as the deactivated state and theUE does not monitor PDCCH for that SCell or transmit/receive othersignaling. However, unlike LTE where the existence of CRS in everysubframe or the existence of periodic CSI-RS enables periodic CSImeasurement at predetermined time instances, a CRS or a periodic CSI-RSmay not exist for a new radio system. Then, the UE needs to be signaleda non-zero power CSI-RS (NZP CSI-RS) configuration for a correspondingdeactivated SCell in order for the UE to measure CSI and provide a CSIreport to the gNB.

A UE can be configured by higher layers a CSI-RS-RNTI for scrambling aCRC of a DCI format that is for brevity referred to as a DCI format C.The UE is also configured by higher layers one or more locations forrespective fields in a DCI format C where each field corresponds eitherto an SCell or to a group of SCells where a respective SCell index orrespective SCell indexes in the group of SCells is configured by higherlayers.

The field is used to indicate an NZP CSI-RS resource configuration for aNZP CSI-RS reception by the UE on a corresponding SCell or group ofSCells that can include all configured cells or all cells that are notactivated. The NZP CSI-RS reception is used by the UE to measure andreport CSI for the SCell or the group of SCells.

The field can include a number of bits equal to ceil(log₂(n_(NZP)+1))where ceil( ) is the ceiling function that rounds a number to a nextlarger integer and n_(NZP) is a number of NZP CSI-RS resourceconfigurations that can be indicated for an SCell by a DCI format C. Forexample, if the NZP CSI-RS resource configuration is limited to one,then a field in a DCI format C includes one bit with, for example, avalue of “0” indicating no NZP CSI-RS reception for a correspondingSCell (or group of SCells) and hence no CSI measurement and reportingand a value of “1” indicating the NZP CSI-RS reception for thecorresponding SCell.

If a UE is capable to simultaneously receive over T cells and the UE hasA active cells, the UE can simultaneously receive NZP CSI-RS in T-Acells. If a number of SCells indicated to a UE by a DCI format C for NZPCSI-RS reception is not larger than T-A, the UE can simultaneouslyreceive NZP CSI-RS in the indicated SCells according to respective NZPCSI-RS resource configurations.

For example, the NZP CSI-RS reception can be over same symbols of a sameslot. When a number of SCells indicated to a UE by a DCI format C forNZP CSI-RS reception is larger than T-A, the UE can simultaneouslyreceive NZP CSI-RS in the first T-A SCells, according to respective cellindexes and according to the respective NZP CSI-RS resourceconfigurations, continue with the next T-A SCells and so on. When the UEcannot receive NZP CSI-RS simultaneously in all indicated SCells and theUE needs to retune the UE's radio-frequency, the NZP CSI-RS reception insuccessive T-A SCells can be in different successive slots that supportZP CSI-RS reception, such as non-uplink slots. A DL BWP for NZP CSI-RSreception in a non-activated cell can be a reference DL BWP such as aninitial DL BWP indicated by higher layers for each respective SCell.

A DCI format C can also include a PUCCH resource (including a slot timeoffset relative to the slot for the reception of DCI format C) for theUE to transmit the associated CSI reports in a PUCCH and a TPC commandto adjust a transmission power of the PUCCH.

FIG. 11 illustrates a flowchart of a method 1100 for a UE to measure andreport CSI for a set of cells according to embodiments of the presentdisclosure. An embodiment of the method 1100 shown in FIG. 11 is forillustration only. One or more of the components illustrated in FIG. 11can be implemented in specialized circuitry configured to perform thenoted functions or one or more of the components can be implemented byone or more processors executing instructions to perform the notedfunctions. Other embodiments are used without departing from the scopeof the present disclosure.

A gNB configures a UE with a RNTI for a DCI format C, a search space setincluding a periodicity for the DCI format C reception, and with alocation of a field in the DCI format C that indicates a configurationfor a NZP-CSI-RS reception or for an activation of a CSI-RS reception incase there is only a single configuration that is provided in advance byhigher layer signaling in step 1410. In addition to an activation of aCSI-RS reception, the field or additional respective fields can includea TPC command for determining a power for a PUCCH transmission thatincludes one or more CSI reports, a corresponding PUCCH resource, and aslot timing offset unless they are configured in advance by higherlayers or specified.

The activation of a CSI reception can be for all cells, or only fornon-activated cells, or only for a group of cells that includes one ormore cells and is configured by higher layers. Upon detection of a DCIformat C, the UE determines whether a corresponding field indicatesactivation of CSI-RS reception for a cell in step 1420. When it does,the UE performs a measurement based on the CSI-RS, obtains a CSI, andreports the CSI for the applicable cells in a PUCCH that the UEtransmits with a power determined using the TPC command and theindicated PUCCH resource and slot timing offset in step 1430.

Reporting of Preferred Configurations

A UE can report one or more configurations for transmissions to aserving gNB or for receptions from the serving gNB that are preferred bythe UE, for example according to the UE's power status. For example,when the UE has full battery power or is connected to a power supply,the UE can request a first configuration that can be beneficial, forexample, for coverage or increased data rates. For example, when the UEhas low battery power, the UE can request a second configuration thatcan prioritize, for example, reduced UE power consumption over increaseddata rates. Parameters in a configuration can include a number oftransmitter antennas or spatial layers, a number of receiver antennas orspatial layers, a number of activated cells, a PDCCH monitoringperiodicity, and so on.

Each of the one or more configurations that a UE reports to a servinggNB can be represented by a value of a field. For example, a field of 2bits can be used to indicate with respective values of “00,” “01,” “10,”and “11,” one of the following four configurations {2 receiver antennas,1 spatial layer, first group of activated cells}, {4 receiver antennas,2 spatial layers, first group of activated cells}, {4 receiver antennas,2 spatial layers, second group of activated cells}, {2 receiverantennas, 2 spatial layers, third group of activated cells}.

A number of preferred configurations that a UE can report can bepredetermined in a system operation, such as for example oneconfiguration, or be configured to the UE by higher layers. When the UEis configured to report more than one preferred configurations, theorder of preference can be according to the order of the correspondingfields in the report. The report of the one or more preferred UEconfigurations can be periodic or triggered by the UE or by the gNB.

For a periodic report, the UE can be configured a reporting periodicityand a PUCCH resource for transmission of a PUCCH that includes thereport. The periodic report of preferred configurations can coincidewith a periodic/semi-persistent CSI report, although with same orsmaller periodicity, and the UE can then combine the two reports in asame PUCCH. When a number of available REs (excluding REs used for DMRStransmission) in a PUCCH resource is not sufficient for controlinformation in a respective PUCCH transmission to achieve a target coderate that, for example, the UE is configured by higher layers, the UEcan prioritize transmission of the configuration report overtransmission of CSI reports.

For a triggered report, the UE can include the report in a MAC controlelement (MAC CE) the UE transmits in a PUSCH. This also enables aserving gNB to determine whether or not the report is correctly received(by performing a CRC check for a reception of an associated transportblock). A report can also be requested by a serving gNB, for examplethrough a field in a DCI format, such as DCI format 0_1 or DCI format1_1.

A serving gNB can indicate a selected configuration to a UE by a MAC CEin a PDSCH transmission to the UE. The configuration can be applicableafter a specified time period that is determined by a time required fora UE to apply a new configuration. For example, the time can be same asa time required for a UE to apply a new TCI state as indicated by a MACCE. To ensure that abrupt changes in coverage do not result to the UEbeing out of coverage when the UE uses a configuration with a reducednumber of receiver antennas, the UE can switch to using the maximumnumber of receiver antennas, such as four receiver antennas, with aperiodicity that can be configured to the UE by higher layers from theserving gNB. For example, in one or more slots per number of slots, suchas 40 slots or every 40 msec, the UE can have all receiver antennasactivated and then deactivate some of the receiver antennas based on theconfiguration indicated by the serving gNB. The number of slots can beconfigured to the UE by higher layers or be defined in the NRspecification of the system operation.

As different receiver antennas can experience different path-loss, forexample due to the UE design or due to external factors such as the UEplacement/orientation or due to blockage by human or other interferenceto the received signal, the UE can report to a serving gNB a CQI or aSINR/RSRP per receiver antenna or per subset of receiver antennas. Thereport can be for a reference cell, such as the PCell, or for any cellthat the UE reports CQI or RSRP. For example, the report can include anRSRP for a first receiver antenna, such as the one with the largestRSRP, and a differential RSRP in quantized steps of, for example, 3 dBfor the remaining receiver antennas. For example, the report can includea CQI for 4 receiver antennas, a CQI for 2 receiver antennas, or a CQIfor 1 receiver antenna. This can provide additional information to aserving gNB for determining a configuration for a number of receiverantennas (and of transmitter antennas) for the UE.

For example, if the RSRP for a second antenna is at least 6 dB smallerthan the RSRP for a first antenna, the gNB can indicate to the UE todeactivate the second receiver antenna. It is also possible for the UEto make such decision independently without informing the gNB if the UEdetermines that an RSRP for one receiver antenna is below apredetermined threshold relative to the RSRP of another receiverantenna.

FIG. 12 illustrates a flowchart of a method 1200 for a UE reporting fordetermining a configuration for a number of UE receiver antennasaccording to embodiments of the present disclosure. An embodiment of themethod 1200 shown in FIG. 12 is for illustration only. One or more ofthe components illustrated in FIG. 12 can be implemented in specializedcircuitry configured to perform the noted functions or one or more ofthe components can be implemented by one or more processors executinginstructions to perform the noted functions. Other embodiments are usedwithout departing from the scope of the present disclosure.

A UE is equipped with N receiver antennas. The UE measures a receptionquality, such as an RSRP or CQI, for each of the N receiver antennas orfor groups of the N receiver antennas in step 1210. The UE reports theRSRP or CQI for the N receiver antennas, or for the groups of the Nreceiver antennas, to a gNB in step 1220. The UE receives, from the gNB,a configuration for a number of receiver antennas, or for a group ofreceiver antennas, for the UE to receive transmissions from the gNB instep 1230. In case the configuration provides a number of receiverantennas, the receiver antennas are the ones equal to the number andhaving the larger reported RSRP.

A configuration can also be implicitly determined by a UE based on theoperating conditions. For example, when the UE switches from a first BWPto a second BWP, such as a default BWP or an initial BWP, the UE canalso switch from a first configuration to a second configuration. TheBWP can be relative to any active cell or only for the primary cell. Forexample, the UE can operate with four receiver antennas when a DL BWP isa first DL BWP, such as a large DL BWP supporting high data rates, andoperate with two receiver antennas when a DL BWP is a second DL BWP,such as a small DL BWP supporting transmission of small data packets tothe UE. Such a UE behavior can be enabled by a serving gNB though arespective configuration by higher layers.

FIG. 13 illustrates a flowchart of a method 1300 for a UE determinationfor a number of UE receiver antennas depending on a corresponding DL BWPaccording to embodiments of the present disclosure. An embodiment of themethod 1300 shown in FIG. 13 is for illustration only. One or more ofthe components illustrated in FIG. 13 can be implemented in specializedcircuitry configured to perform the noted functions or one or more ofthe components can be implemented by one or more processors executinginstructions to perform the noted functions. Other embodiments are usedwithout departing from the scope of the present disclosure.

As illustrated in FIG. 13, a UE receives a configuration for a firstnumber of receiver antennas when a first DL BWP is the activated DL BWPand for a second number of receiver antennas when a second DL BWP is theactivated DL BWP in step 1310. The UE determines whether an activated DLBWP is the first DL BWP or the second DL BWP in step 1320. When theactivated DL BWP is the first DL BWP, the UE uses the first number ofreceiver antennas in step 1330. When the activated DL BWP is the secondDL BWP, the UE uses the second number of receiver antennas in step 1340.The UE can further select the first number and the second number to bethe ones corresponding to the receiver antennas where the UE measuresthe larger RSRP.

A gNB can provide an adaptation for a configuration oftransmissions/receptions by a UE using either higher layer signaling,such as a MAC CE or RRC, or layer 1 (physical layer) signaling. Thelatter is preferable when minimum latency for an adaptation of aconfiguration is material in achieving most gains from the adaptation.When a number of bits required to provide an adaptation for aconfiguration of transmissions/receptions by a UE is more than a few orwhen the adaptation is not frequent, a re-interpretation of aUE-specific DCI format to indicate the adaptation can be a moreefficient choice than using one or more fields in a UE-common DCI formator in a UE-specific DCI format. This is because a UE-specific DCI formatthat can be reinterpreted to indicate an adaptation of a configurationcan be transmitted by a gNB to a UE on demand instead of alwaysreserving fields to indicate the adaptation of the configuration for theUE in a UE-common DCI format or in a UE-specific DCI format when anactual use of those fields is not frequent.

The reinterpretation of a UE-specific DCI format to indicate anadaptation of a configuration to the UE instead of scheduling a PDSCHreception or PUSCH transmission can be by an explicit field of 1 bit orby setting existing fields of the UE-specific DCI format to specificvalues. For example, in a DCI format 0_1, a field indicating absence ofuplink shared channel (UL-SCH) transmission can be set (no UL-SCH) and afield indicating a request for an A-CSI report is not set (no A-CSIreport).

For example, a field indicating a redundancy version (RV) can be set toindicate RV 3 or RV 1 and a field indicating transmission of a newtransport block (NDI) can be set to indicate a new transport block. Whenthe DCI format is interpreted to convey an adaptation of a configurationfor transmission/reception parameters for a UE, the remaining bits ofthe DCI format (other than the bits used for the interpretation and theCRC bits) can be used to indicate the adaptation with some bits beingreserved/not used in case the adaptation can be indicated with fewerbits than the remaining bits of the DCI format.

The adapted configuration can include a number of receiver antennas, anumber of transmitter antennas, a number of layers, a number ofactivated cells or BWPs, the parameters for a C-DRX period (On Durationand Inactivity Timer), the parameters for PDCCH monitoring, otherparameters related to configurations of search space sets such as ascaling of PDCCH candidates, and so on. The adaptation of theconfiguration can become effective either immediately or after apredetermined time from a time the UE provides HARQ-ACK information inresponse to the DCI format detection.

A fallback operation to recover from potential errors can be supportedby the UE using a configuration for transmissions/receptions that waspreviously provided by higher layers or is default at predetermined orconfigured time periods, such as every 40 msec, or when the UE monitorsUE-specific DCI formats in a common search space, and so on.

A processing time associated with scheduling PDSCH/PUSCHreception/transmission (e.g., N0/N2 symbols) can be set. N0 or N2indicate a minimum processing time needed for a UE to receive a PDSCH orto transmit a PUSCH, respectively. The delay between a PDCCH and anassociated PDSCH/PUSCH reception/transmission, i.e., K1/K2, needs to belarger than N0/N2. The default values of N0/N2 can be predefined in asystem operation or can be provided to a UE by higher layer signaling.For example, a default value of N0/N2 can be 1 slot. The UE can go tolight sleep for a period no larger than N0/N2 after detecting acorresponding DCI format in a PDCCH in order to save power.

To improve UE power saving gains, a serving gNB can transmit to a UEcontrol information that indicates a dynamic update of N0/N2 in order toadapt to different power savings gain targets or different latencyrequirements. For example, when the control information is 1 bit, “0”can indicate doubling of N0/N2 relative to the predetermined values,such as N0=2×N0_default or N2=2×N0_default, while “1” can indicateN0=max(N0/2, N0_default) or N2=(N2/2, N2_default). N0_default andN2_default are the values of N0 and N2 that are provided to the UE byhigher layers or are predetermined in the system operation.

When a UE is configured for operation with CA, activation/deactivationof SCells can be combined with adaptation on N0/N2. When N0/N2 is largerthan a threshold, T{circumflex over ( )}N0/T{circumflex over ( )}N2,SCells without scheduled PDSCH/PUSCH reception/transmission for the UEin a PDCCH monitoring period on a scheduling cell can be deactivated.Conversely, when the UE detects a DCI format in a PDCCH that the UEreceives on a scheduling cell and schedules PDSCH/PUSCHreception/transmission on an SCell, the UE activates the SCell. The UEcan also activate the SCell whenever the UE is triggered or configuredfor CSI-RS reception or SRS transmission on the SCell.

FIG. 14 illustrates a flowchart of a method 1400 for adaptation ofprocessing time for scheduling PDSCH/PUSCH reception/transmission on anSCell combined with an activation or deactivation of the SCell accordingto embodiments of the present disclosure. An embodiment of the method1400 shown in FIG. 14 is for illustration only. One or more of thecomponents illustrated in FIG. 14 can be implemented in specializedcircuitry configured to perform the noted functions or one or more ofthe components can be implemented by one or more processors executinginstructions to perform the noted functions. Other embodiments are usedwithout departing from the scope of the present disclosure.

A default configuration for a set of slot timing values K1 associatedwith only the primary cell and SCS of 15 KHz can be provided to a UE byhigher layers, such as a parameter dl_DataTo_UL_ACK. When a serving gNBindicates to a UE to switch from an active BWP with SCS_j to and activeBWP with SCS_i, a size/cardinality of K1, denoted as |K1|, can beadapted to |K1|*(SCS_j/SCS_i) and the range for elements in the set ofK1 values, [0, v_i], can be adapted to [0, v_j]*(SCS_j/SCS_i).

Slot timing values of K1 can be adapted to traffic load indicated bynumber of activated cells. Multiple numbers of activated cells can bepredefined and can correspond to “CA levels.” For example, CA level 0/CAlevel 1/CA level 2/CA level 3/CA level 4, denoted as, L{circumflex over( )}CA_0/L{circumflex over ( )}CA_1/L{circumflex over( )}CA_2/L{circumflex over ( )}CA_3/L{circumflex over ( )}CA_4, can bepredefined as associated with a number of 1/2/4/8/16 activated cells,respectively. When a CA level changes from L{circumflex over ( )}CA_i toL{circumflex over ( )}CA_j due to activation or deactivation of cellsfor adapting to different traffic loads, a size/cardinality of K1,denoted as |K1|, can be adapted to |K1|*(L{circumflex over( )}CA_j/L{circumflex over ( )}CA_i) and the range for elements in theset of K1 values, [0, v_i], can be adapted to [0, v_j]*(L{circumflexover ( )}CA_j/L{circumflex over ( )}CA_i).

As illustrated in FIG. 14, a UE receives a configuration on defaultprocessing time on scheduling PDSCH/PUSCH, N0/N2, and the UE does notexpect any K1/K2 larger than N0/N2 in step 1410. In step 1420, the UEreceives L1 control information to scale N0/N2. In step 1430, the UEdetermines N0/N2>T{circumflex over ( )}N0/T{circumflex over ( )}N2. WhenN0/N2>T{circumflex over ( )}N0/T{circumflex over ( )}N2 in step 1430,the UE in step 1440 deactivates SCells that are not indicated forPDSCH/PUSCH scheduling and activates SCells that are indicated forPDSCH/PUSCH scheduling.

FIG. 15 illustrates a flowchart of a method 1500 for an adaption of slottiming values K1 together with BWP switching and SCellactivation/deactivation according to embodiments of the presentdisclosure. An embodiment of the method 1500 shown in FIG. 15 is forillustration only. One or more of the components illustrated in FIG. 15can be implemented in specialized circuitry configured to perform thenoted functions or one or more of the components can be implemented byone or more processors executing instructions to perform the notedfunctions. Other embodiments are used without departing from the scopeof the present disclosure.

When a UE is configured for operation with dual connectivity (DC), a gNBfor the master cell group (MCG) and a gNB for the secondary cell group(SCG) operate independently and an adaptation for a configuration oftransmission/reception parameters for a UE is typically required on boththe MCG and the SCG. For example, when both the MCG and the SCG operateon a same frequency range, such as below 6 GHz, the UE needs to operatewith either 2 Rx antennas or with 4 Rx antennas on both MCG and SCG andcoordination between the MCG and the SCG for a number of UE receiverantennas is needed.

When PDCCH monitoring occasions are adapted on the MCG or the SCG, it isbeneficial to have a similar adaptation on the SCG or the MCG,respectively, so that the UE monitors PDCCH on both the MCG and the SCGat a same time or is on sleep mode on the MCG and the SCG at a sametime. For example, the MCG and the SCG can exchange over a backhaul linkrespective C-DRX cycles for a UE or the MCG can indicate to the SCG theC-DRX cycle configuration for the UE. Further, it is beneficial that theMCG and the SCG configure a UE to perform measurements when the UE is inC-DRX active time on both MCG and SCG. For example, the MCG and the SCGcan exchange over a backhaul link CSI-RS patterns or the MCG can selectand indicate to the SCG a CSI-RS pattern from a set of CSI-RS patternsindicated to the MCG by the SCG.

To reduce a likelihood that a UE becomes power limited for transmissionsto both the MCG and the SCG, the MCG and the SCG can exchange over abackhaul link PUSCH, PUCCH, or SRS transmission patterns for periodic orsemi-persistent PUSCH, PUCCH, or SRS transmissions. Then, when there isa large likelihood that the UE can be power limited for transmissions toboth the MCG and the SCG, such as when the UE reports a small RSRP(large path-loss) for at least one CG, the SCG (or the MCG) can select apattern for periodic or semi-persistent PUSCH, PUCCH, or SRStransmissions that does not overlap in time with a corresponding patternon the MCG.

Conversely, when there is a small likelihood that the UE can be powerlimited for transmissions to both the MCG and the SCG, such as when theUE reports a large RSRP (small path-loss) for both CGs, the SCG (or theMCG) can select a pattern for periodic or semi-persistent PUSCH, PUCCH,or SRS transmissions that overlaps in time with a corresponding patternon the MCG so that the UE can increase a time when the UE does nottransmit (with the exception of dynamically triggered transmissions).

In case the UE provides assistance information associated with anadaptation of transmission/reception parameters, the UE can provideseparate assistance information to the MCG and to the SCG or the UE canprovide the assistance information associated with a configuration onthe MCG/SCG also to the SCG/MCG. In the former case, the SCG/MCG canexchange the assistance information with the MCG/SCG through a backhaullink. When only the MCG can decide on an adapted configuration, the SCGcan request an adapted configuration to the MCG through the backhaullink. Based on the request or, in general, based on an independentdecision by the MCG, the MCG can inform the SCG of an adaptedconfiguration.

In one example for an adaptation of a configuration fortransmissions/receptions for a UE configured for DC operation, the MCGor the SCG can signal to the UE an adaptation of the configuration andcan inform the SCG or the MCG, respectively, through backhaul signaling.To reduce a delay for a CG to communicate with the UE using the adaptedconfiguration, some of the configurations, such as a configuration for aPDCCH monitoring periodicity in C-DRX cycles or for parameters of aC-DRX configuration, can have a nested structure where one configurationis a superset or a subset of another configuration.

For example, a PDCCH monitoring periodicity can be 0.5 msec, 1 msec, 2msec, or 4 msec (or 1 slot, 2 slots, 4 slots, or 8 slots for 30 kHz SCS)and regardless of an adaptation a CG knows that the UE monitors PDCCHevery 4 msec (or every 8 slots for 30 kHz SCS). In this manner, a CG cancontinue to schedule the UE using at least the common values of aparameter for each configuration until the UE informs the CG that the UEapplies the adapted configuration. In case a configuration isCG-specific, such as for example a number of SCells, the adaptationprocess can be contained within the CG. In case a configuration is for aparameter such as a number of receiver antennas, a CG can make anyassumption on the configuration the UE applies although a conservativeassumption for a smaller possible number of receiver antennas ispractically justifiable.

In one example for an adaptation of a configuration fortransmissions/receptions for a UE configured for DC operation, the MCGor the SCG can indicate to the UE an adaptation of the configuration. Toreduce a delay associated with backhaul signaling, the UE can act as arelay between the two CGs and signal an adapted configuration that theUE received from one CG to the other CG.

To facilitate the signaling, the possible configurations can bepredetermined in a set of configurations, either by specification in thesystem operation or by higher layer signaling, and the UE can signal anelement from the set of configurations. A configuration can include, forexample, a number of search space sets, parameters for each search spaceset, a number of receiver antennas, and so on.

For example, for a set with 4 configurations, the UE can signal 2 bitsto indicate one configuration from the 4 configurations. The UE canreport the adapted configuration to a CG in a PUCCH transmission on aresource and slot offset indicated by the CG or in a PUSCH transmissionin the CG. To minimize PUCCH resource overhead, an adaptation of aconfiguration can be restricted to occur at predetermined time instancessuch as every 10 msec or every 40 msec starting from frame zero or froma predetermined slot offset or frame offset relative to slot 0 in frame0 that is provided to the UE by higher layers.

The UE can provide to one CG additional information related to thecommunication with the other CG. For example, together with a bufferstatus report (BSR) for a first CG, the UE can provide a BSR for asecond CG to the first CG. The first CG can use the information for theBSR for the second CG to determine an adaptation of a configuration fortransmissions/receptions from the UE as the BSR for the second CG can beused to determine likelihood that the UE has active communication withthe second CG. Also, BSR for a UE can be exchanged between a MN and a SNthrough a backhaul link.

For example, together with an RSRP report for each receiver antenna forreceptions on the first CG, the UE can provide to the first CG an RSRPreport for each receiver antenna for receptions on the second CG. Thefirst CG can use the information for the RSRP reports for the second CGto determine an adaptation for a number of receiver antennas.

For operation with DC, the MCG can indicate to the SCG through backhaulsignaling a maximum number of monitored PDCCH candidates per slot,M_(PDCCH,SCG,) and a maximum number of non-overlapped CCEs per slotC_(PDCCH,SCG). The MCG can also indicate to the UE the maximum number ofmonitored PDCCH candidates per slot and the maximum number ofnon-overlapped CCEs per slot for the SCG and the UE can derive thecorresponding maximum numbers for the MCG, M_(PDCCH,MCG) andC_(PDCCH,MCG), from the difference relative to a corresponding totalmaximum numbers per slot, M_(PDCCH) and C_(PDCCH), asM_(PDCCH,MCG)=M_(PDCCH)−M_(PDCCH,SCG) andC_(PDCCH,MCG)=C_(PDCCH)−C_(PDCCH,SCG), or M_(PDCCH,MCG) andC_(PDCCH,MCG) can also be signaled to the UE.

In one example, the MCG and the SCG can provide to the UE correspondingmaximum numbers for the monitored PDCCH candidates per slot andnon-overlapped CCEs per slot. Then, the MCG can control when the UEmonitors PDCCH on the SCG and can partition a number of PDCCH candidatesand non-overlapped CCEs between the MCG and the SCG.

In one example, when cells on the SCG operate on unpaired spectrum suchas for example using a TDD UL/DL configuration, the MCG can allocate amaximum number of monitored PDCCH candidates and non-overlapping CCEs tothe SCG and still use the maximum number of monitored PDCCH candidatesand non-overlapping CCEs by configuring the search space sets so thatthe UE monitors PDCCH on the MCG when the slot has UL direction on cellsof the SCG (this assumes that the SCG does not change an UL/DLconfiguration without informing the MCG). In general, at PDCCHmonitoring occasions on a cell where corresponding CORESETs include ULsymbols, a UE can allocate a corresponding PDCCH monitoring capabilityto one or more other cells.

In one example, the MCG can reserve a number of monitored PDCCHcandidates per slot and a number of non-overlapping CCEs per slot foruse on the MCG and allocate a remaining number of monitored PDCCHcandidates per slot, relative to the maximum number of monitored PDCCHcandidates per slot, and a remaining number of non-overlapping CCEs perslot, relative to the maximum number of non-overlapped CCEs per slot tothe SCG.

FIG. 16 illustrates a call flow 1600 for an MCG and an SCG to exchangeinformation to determine respective configurations for communicatingwith a UE according to embodiments of the present disclosure. Anembodiment of the call flow 1600 shown in FIG. 16 is for illustrationonly. One or more of the components illustrated in FIG. 16 can beimplemented in specialized circuitry configured to perform the notedfunctions or one or more of the components can be implemented by one ormore processors executing instructions to perform the noted functions.Other embodiments are used without departing from the scope of thepresent disclosure.

An MCG configures a UE for a DC operation with an SCG and provides tothe SCG through a backhaul link a configuration fortransmissions/receptions by the UE on the MCG in step 1610. Theconfiguration can include, for example, a number of antennas, a set ofparameters for a C-DRX cycle, a total number of PDCCH candidates the UEis configured to monitor on the SCG and so on. The SCG provides throughthe backhaul link to the MCG a requested configuration or parameters fordetermining a configuration for transmissions/receptions by the UE onthe SCG in step 1620. The MCG provides through the backhaul link a setof one or more configurations for the SCG to use from communicating withthe UE in step 1630. When the set includes more than one configuration,the SCG can inform the MCG of the selected configuration in step 1640.

For an operation with DC, an MCG is controlled by a master node (MN) andan SCG is controlled by a secondary node (SN). When a UE is configuredwith DC operation, it is necessary for the MN, the SN, and the UE tohave a same understanding for a number of PDCCH candidates the UE isexpected to monitor per slot and for a number of non-overlapped CCEs theUE is expected to be able to perform channel estimation per slot.

A first approach is for a MN and a SN to partition N_(cells) ^(cap)between them where a capability of N_(cells,MCG) ^(cap) is used by theMN and a capability of N_(cells,SCG) ^(cap) is used by the SN(N_(cells,MCG) ^(cap)+N_(cells,SCG) ^(cap)≤N_(cells) ^(cap)) Thisembodiment requires backhaul signaling from the MN to the SN and higherlayer signaling to the UE for a value of N_(cells,SCG) ^(cap) (then,N_(cells,MCG) ^(cap)=N_(cells) ^(cap)−N_(cells,SCG) ^(cap)). The valueof N_(cells,MCG) ^(cap) may also be separately included in the higherlayer signaling, for example to enable N_(cells,MCG)^(cap)+N_(cells,SCG) ^(cap)<N_(cells) ^(cap).

Then, for a capability of a UE to monitor PDCCH (on the active BWPs) forN_(cells,MCG) ^(cap) cells on the MN and N_(cells,SCG) ^(cap) on the SN,the UE is expected to monitor a total of M_(PDCCH,MCG)^(total,μ)=min{N_(cells,MCG) ^(DL,μ)·M_(PDCCH) ^(max,slot,μ),└N_(cells,MCG) ^(cap)·M_(PDCCH) ^(max,slot,μ)·N_(cells,MCG)^(DL,μ)/Σ_(μ=0) ³N_(cells,MCG) ^(DL,μ)┘} PDCCH candidates for DCIformats with different sizes and/or different corresponding DM-RSscrambling sequences per slot over N_(cells,MCG) ^(DL,μ) cells of the MNwith SCS configuration μ.

The UE is expected to monitor a total of M_(PDCCH,SCG) ^(total,μ)=min{N_(cells,SCG) ^(DL,μ)·M_(PDCCH) ^(max,slot,μ), └N_(cells,SCG)^(cap)·M_(PDCCH) ^(max,slot,μ)·N_(cells,SCG) ^(DL,μ)/Σ_(μ=0)³N_(cells,SCG) ^(DL,μ)┘} PDCCH candidates for DCI formats with differentsizes and/or different corresponding DM-RS scrambling sequences per slotover N_(cells,SCG) ^(DL,μ) cells of the SN with SCS configuration μ.

Similar, the UE is expected to monitor a total of C_(PDCCH,MCG)^(total,μ)=min {N_(cells,MCG) ^(DL,μ)·CM_(PDCCH) ^(max,slot,μ),└N_(cells,MCG) ^(cap)·C_(PDCCH) ^(max,slot,μ)·N_(cells,MCG)^(DL,μ)/Σ_(μ=0) ³N_(cells,MCG) ^(DL,μ)┘} non-overlapping CCEs for PDCCHreceptions scheduling over N_(cells,MCG) ^(DL,μ) cells of the MN withSCS configuration μ.

The UE is expected to monitor a total of C_(PDCCH,MCG) ^(total,μ)=min{N_(cells,MCG) ^(DL,μ)·C_(PDCCH) ^(max,slot,μ), └N_(cells,MCG)^(cap)·C_(PDCCH) ^(max,slot,μ)·N_(cells,MCG) ^(DL,μ)/Σ_(μ=0)³N_(cells,MCG) ^(DL,μ)┘} non-overlapping CCEs for PDCCH receptionsscheduling over N_(cells,SCG) ^(DL,μ) cells of the SN with SCSconfiguration μ.

A second approach that avoids higher layer signaling to the UE is forthe MN and the SN to exchange the respective values of N_(cells,MCG)^(DL,μ) and N_(cells,SCG) ^(DL,μ) for a UE, or for the MN to indicatethe value of N_(cells,SCG) ^(DL,μ) to the SN. Then, N_(cells)^(DL,μ)=N_(cells,MCG) ^(DL,μ) +N_(cells,SCG) ^(DL,μ) and the UE cantreat all cells as if the cells are in a single CG for determining anumber of PDCCH candidates or a number of non-overlapping CCEs that theUE is expected to monitor on a cell with SCS configuration μ.

For example, of M_(PDCCH) ^(total,μ)=min {N_(cells) ^(DL,μ)·M_(PDCCH)^(max,slot,μ), └N_(cells) ^(cap)·M_(PDCCH) ^(max,slot,μ)·N_(cells)^(DL,μ)/Σ_(μ=0) ³N_(cells) ^(DL,μ)┘} and C_(PDCCH) ^(total,μ)=min{N_(cells) ^(DL,μ)·C_(PDCCH) ^(max,slot,μ), └N_(cells) ^(cap)·C_(PDCCH)^(max,slot,μ)·N_(cells) ^(DL,μ)/Σ_(μ=0) ³N_(cells) ^(DL,μ)┘}. The SNalso obtains N_(cells) ^(cap) either from the MN or from the UE.

An issue with the second embodiment is whether the SCS configuration μof the active DL bandwidth part (BWP) can be used as reference for acell when BWP switching can be triggered by a DCI format. As one cellgroup cannot know a BWP switching triggered by a DCI format on a cell ofthe other cell group, having the active DL BWP providing the SCSreference configuration for a cell can be problematic.

Alternative example includes the usage of the SCS configuration for theBWP indicated to the UE by higher layer parameterfirstActiveDownlinkBWP, or the SCS configuration for the BWP with thesmallest index and so on, as long as the DL BWP providing the SCSreference configuration for a cell is determined by higher layersignaling. Conversely, for operation with a single CG, the SCS referenceconfiguration for a cell can be the one corresponding to the active DLBWP.

A third approach is to limit the total number of cells that can beconfigured to a UE when the UE is also configured for DC operation to nomore than 4 that is assumed to be a minimum UE capability when a UE isalso configured with carrier aggregation (CA) in at least one cellgroup. That is, a UE does not expect to process PDCCH scheduling PDSCHor PUSCH in more than 4 cells. The limit on the number of cells can bemore than 4 when the UE is configured only for CA operation withoutbeing configured for DC operation.

Instead of the MN and the SN exchanging a number of respective cellswith a corresponding numerology that are configured/activated to a UEfor operation in the respective CGs (MCG and SCG), a functionallyequivalent approach is for the MN to inform the SN of a number of PDCCHcandidates and/or non-overlapping CCEs that are reserved for use on theMN or that are available for use on the SN.

The number can be either the total one across all SCS configurations orper SCS configuration. In the former case, the SN can derive a number ofPDCCH candidates and/or non-overlapping CCEs available for use in theSCG by subtracting the corresponding number informed by the MN from thetotal number determined from the UE capability. The SN can also informthe MN of a corresponding number of PDCCH candidates and/ornon-overlapping CCEs that are allocated to the UE for communication inthe respective CG.

In one example, for a UE capability to monitor 4×{44, 36, 22, 20} PDCCHcandidates per slot for SCS configuration μ of {0, 1, 2, 3}, the MN caninform the SN that the SN can configure the UE a maximum of {2×44, 3×36,4×22, 4×20} PDCCH candidates for cells of the SCG. For example, for a UEcapability to monitor 4×{44, 36, 22, 20} PDCCH candidates per slot forSCS configuration μ of {0, 1, 2, 3}, the MN can inform the SN that theSN can configure the UE a maximum of {100, 50, 4×22, 4×20} PDCCHcandidates. For example, for a UE capability to monitor 4×{44, 36, 22,20} PDCCH candidates per slot for SCS configuration μ of {0, 1, 2, 3},the MN can inform the SN that the SN can configure the UE a maximum of{50%, 50%, 100%, 100%} for PDCCH candidates relative to the UEcapability and the signaling can map to a predetermined set ofpercentages such as a 3-bit signaling mapping to {0, 15, 30, 45, 60, 75,90, 100}%, similar for an allocation of a number of non-overlapping CCEsper slot.

For determining search space sets to monitor, at least for the secondapproach, a UE allocates search space sets to the PCell of the MCG andthe PSCell of the SCG in an alternating manner starting from the MCG.For example, the following pseudo-code can be used for the UE toallocate monitored PDCCH candidates to USS sets for the PCell and forthe PSCell having an active DL BWP with SCS configuration μ.

Denote by V_(CCE)(S_(uss)(j, cg)) the set of non-overlapping CCEs forsearch space set S_(uss)(j,cg) of CG with index cg, where cg=0 for theMCG and cg=1 for the SCG, and by C(V_(CCE)(S_(uss)(j, cg))) thecardinality of V_(CCE)(S_(uss)(j, cg)) of CG with index cg where thenon-overlapping CCEs for search space set S_(uss)(j,cg) are determinedconsidering the monitored PDCCH candidates for the CSS sets and themonitored PDCCH candidates for all search space sets S_(uss)(k,cg),0≤k≤j. TABLE 1 shows some configuration.

TABLE 1 Setting parameters Set M_(PDCCH) ^(uss) = min(M_(PDCCH)^(max,slot,μ), M_(PDCCH) ^(total,slot,μ)) − M_(PDCCH) ^(css) SetC_(PDCCH) ^(uss) = min(C_(PDCCH) ^(max,slot,μ), C_(PDCCH)^(total,slot,μ)) − C_(PDCCH) ^(css) Set j = 0 Set cg = 0 while Σ_(L)M_(S) _(uss)(j,cg)^((L)) ≤ M_(PDCCH) ^(uss) AND C(V_(CCE)(S_(uss)(j,cg))) ≤ C_(PDCCH) ^(uss)      allocate Σ_(L) M_(S) _(uss)(j,cg)^((L))monitored PDCCH candidates to      USS set S_(uss)(j, cg)      M_(PDCCH)^(uss) = M_(PDCCH) ^(uss) − Σ_(L) M_(S) _(uss)(j,cg)^((L));     C_(PDCCH) ^(uss) = C_(PDCCH) ^(uss) − C(V_(CCE)(S_(uss)(j, cg)));     cg = (cg + 1) mod 2;      if cg = 0      j = j + 1 ;      end ifend while

TABLE 2 shows a UE's operation based on some of conditions.

TABLE 2 UE operation When a UE has a set of activated cells on a CG, andis provided an UL/DL configuration for a first activated cell from theset of activated cells, and is configured a PDCCH monitoring occasion ina set of symbols of a slot on the first activated cell, and isconfigured a PDCCH monitoring occasion in the set of symbols of the sloton one or more activated cells, from the set of activated cells, otherthan the first activated cell, and determines a first number of PDCCHcandidates for the PDCCH monitoring occasion, and at least one symbolfrom the set of symbols of the slot is an UL symbol on the firstactivated cell, and each symbol from the set of symbols of the slot is aDL symbol or a flexible symbol on the one or more activated cells, theUE does not monitor PDCCH candidates in the set of symbols of the sloton the first activated cell, and allocates a second number of PDCCHcandidates, from the first number of PDCCH candidates, to the one ormore activated cells from the set of activated cells if the number ofPDCCH candidates on the one or more activated cells is smaller than themaximum number of PDCCH candidates per cell.

As illustrated in TABLE 2, the UE behavior for PDCCH candidates alsoapplies for non-overlapping CCEs in a similar manner. As illustrated inTABLE 2, the UE behavior can be further conditioned on all symbols ofthe slot on the first activated cell being UL symbols. As illustrated inTABLE 2, the UE behavior can be extended for an activated cell of theMCG (or of the SCG) in case of synchronous operation at least for sameSCS configurations on all scheduling cells of the MCG and the SCG. Thatis, when a slot for the activated cell of the MCG (or of the SCG)includes only UL symbols, and each other activated cell of the MCG (orof the SCG) that includes at least one PDCCH monitoring occasion in theslot with each symbol for the at least one PDCCH monitoring occasionbeing a DL symbol or flexible symbol is allocated the maximum number ofPDCCH candidates per slot that the UE can allocate a number of└N_(cells,MCG) ^(cap)·M_(PDCCH) ^(max,slot,μ)·N_(cells,MCG)^(DL,μ)/Σ_(μ=0) ³N_(cells,MCG) ^(DL,μ┘−N) _(cells, MCG) ^(DL,μ)·M_(PDCH)^(max,slot,μ) PDCCH candidates to cells of the SCG in the slot (orallocate a number of └N_(cells,SCG) ^(cap)·M_(PDCCH)^(max,slot,μ)·N_(cells,SCG) ^(DL,μ)/Σ_(μ=0) ³N_(cells,SCG) ^(DL,μ┘−N)_(cell,SCG) ^(DL,μ)·M_(PDCCH) ^(max,slot,μ) PDCCH candidates to cells ofthe MCG in the slot).

In addition to splitting a UE capability for PDCCH monitoring between anMCG and an SCG, another UE capability that needs to be split between theCGs is a maximum number of simultaneous CSI reports that the UE canobtain and provide across all cells of the MCG and the SCG. For example,for a CA operation, a UE can declare/report a capability to process amaximum number of simultaneous CSI reports (perform CSI-RS measurements)across all cells by a value N_(cells) ^(cap,CSI) of higher layerparameter simultaneousCSI-ReportsAllCC.

For dual connectivity operation, the UE can be provided, for examplefrom the MN, a value N_(cells,MCG) ^(cap,CSI) for higher layer parametersimultaneousCSI-ReportsAllCC_MCG indicating a maximum number ofsimultaneous CSI reports that the UE should be able to process acrossall cells of the MCG and a value N_(cells,SCG) ^(cap,CSI) for higherlayer parameter simultaneousCSI-ReportsAllCC_SCG indicating a maximumnumber of simultaneous CSI reports that the UE should be able to processacross all cells of the SCG.

The MN can also inform the SN, for example through backhaul signaling,of the value N_(cells,SCG) ^(cap,CSI) of higher layer parametersimultaneousCSI-ReportsAllCC_SCG and, possibly, of the valueN_(cells,MCG) ^(cap,CSI) of higher layer parametersimultaneousCSI-ReportsAllCC_MCG.

For example, N_(cells,MCG) ^(cap,CSI)+N_(cells,SCG) ^(cap,CSI)=N_(cells)^(cap,CSI). It is also possible that for operation with dualconnectivity, the UE reports separate capabilities for the MCG and theSCG to indicate a maximum number of simultaneous CSI reports that the UEcan provide across all cells of the MCG and the SCG, respectively. Thiscan also apply for a PDCCH monitoring capability where the UE can reporta higher layer parameter pdcch-BlindDetectionCA_MCG and a higher layerparameter pdcch-BlindDetectionCA_SCG for a number of cells on the MCGand the SCG, respectively, that the UE can monitor a maximum number ofPDCCH candidates per slot and per cell. For example, the UE can report avalue N_(cells,MCG,UE) ^(cap,CSI) for a higher layer parametersimultaneousCSI-ReportsAllCCMCG_UE and a value N_(cells,SCG,UE)^(cap,CSI) for a higher layer parametersimultaneousCSI-ReportsAllCCSCG_UE. For example, N_(cells,MCG,UE)^(cap,CSI)+N_(cells,MCG,UE) ^(cap,CSI)≥N_(cells) ^(cap,CSI). Forexample, the UE can report a value N_(cells,MCG) ^(cap) for higher layerparameter pdcch-BlindDetectionCA_MCG and a value N_(cells,SCG) ^(cap)for higher layer parameter pdcch-BlindDetectionCA_SCG.

A gNB can include a search space determination in a configuration of asearch space set to a UE. For example, a search space determination canbe according to Equation 1 or according to a nested search space. Afirst search space set can be configured a first search space, such asin Equation 1, for a determination of CCEs for corresponding PDCCHcandidates and a second search space can be configured a second searchspace, such as a nested search space, for a determination of CCEs forcorresponding PDCCH candidates.

A configuration of a search space determination can also be conditionedon a UE supporting multiple services, such as a multicast-broadcastbroadband (MBB) service and an ultra-reliability low latencycommunication (URLLC) service. Then, in a UE-specific search space set(USS set) where a UE is configured to monitor PDCCH with DCI format(s)associated with MBB service and PDCCH with DCI format(s) associated withURLLC service, or configured to monitor PDCCH with DCI format(s)associated only with URLLC service, the UE can use a nested search spaceto determine CCEs for the PDCCH candidates while in a USS set where theUE is configured to monitor PDCCH with DCI format(s) associated onlywith MBB service, the UE can use a search space according to Equation 1to determine CCEs for the PDCCH candidates.

Although the present disclosure has been described with an exemplaryembodiment, various changes and modifications may be suggested to oneskilled in the art. It is intended that the present disclosure encompasssuch changes and modifications as fall within the scope of the appendedclaims.

None of the description in this application should be read as implyingthat any particular element, step, or function is an essential elementthat must be included in the claims scope. The scope of patented subjectmatter is defined only by the claims. Moreover, none of the claims areintended to invoke 35 U.S.C. § 112(f) unless the exact words “means for”are followed by a participle.

What is claimed is:
 1. A method for a user equipment (UE) to receive physical downlink control channels (PDCCHs) from a master node (MN) or from a secondary node (SN), the method comprising: receiving an indication for a first number of cells N_(cells,MCG) ^(cap) and for a second number of cells N_(cells,SCG) ^(cap), wherein MCG denotes a master cell group for the MN and SCG denotes a secondary cell group for the SN; determining a first total number of PDCCH candidates M_(PDCCH,MCG) ^(total,μ) for N_(cells,MCG) ^(DL,μ) downlink (DL) cells of the MN over a time period according to N_(cells,MCG) ^(cap), wherein μ is a subcarrier spacing (SCS) configuration for an active bandwidth part (BWP) for each of the N_(cells,MCG) ^(DL,μ) DL cells; and determining a second total number of PDCCH candidates M_(PDCCH,SCG) ^(total,μ) for N_(cells,SCG) ^(DL,μ) DL cells of the SN over the time period according to N_(cells,SCG) ^(cap), wherein μ is a SCS configuration for the active BWP for each of the N_(cells,SCG) ^(DL,μ) DL cells.
 2. The method of claim 1, wherein the time period is one slot for SCS configuration μ.
 3. The method of claim 2, wherein: the first total number of PDCCH candidates M_(PDCCH,MCG) ^(total,μ) is determined as M_(PDCCH,MCG) ^(total,μ)=min {N_(cells,MCG) ^(DL,μ)·M_(PDCCH) ^(max,slot,μ), └N_(cells,MCG) ^(cap)·M_(PDCCH) ^(max,slot,μ)·N_(cells,MCG) ^(DL,μ)/Σ_(μ=0) ³N_(cells,MCG) ^(DL,μ)┘}; M_(PDCCH) ^(max,slot,μ) is a maximum number of PDCCH candidates per slot for a cell from the N_(cells,MCG) ^(DL,μ) DL cells; └x┘ is a ‘floor’ function that provides a largest integer that is smaller than x; and min{x, y} is a ‘minimum’ function that provides a smaller of x, y.
 4. The method of claim 1, further comprising: receiving the PDCCH candidates for the N_(cells,MCG) ^(DL,μ) DL cells of the MN according to M_(PDCCH,MCG) ^(total,μ); and receiving the PDCCH candidates for the N_(cells,SCG) ^(DL,μ) DL cells of the SN according to M_(PDCCH,SCG) ^(total,μ).
 5. The method of claim 1, further comprising: determining a first total number of non-overlapped CCEs C_(PDCCH,MCG) ^(totoal,μ) for the N_(cells,MCG) ^(DL,μ) DL cells of the MN over the time period according to N_(cells,MCG) ^(cap); and determining a second total number of non-overlapped CCEs C_(PDCCH,SCG) ^(total,μ) for the N_(cells,SCG) ^(DL,μ) DL cells of the SN over the time period according to N_(cells,SCG) ^(cap).
 6. The method of claim 1, further comprising: transmitting an indication for a number of cells N_(cells) ^(cap), wherein N_(cells,MCG) ^(cap)+N_(cells,SCG) ^(cap)≤N_(cells) ^(cap).
 7. The method of claim 1, wherein the indication for the second number of cells N_(cells,SCG) ^(cap) is transmitted from the MN to the SN.
 8. A base station comprising: a transmitter configured to transmit an indication for a first number of cells N_(cells,MCG) ^(cap) and for a second number of cells N_(cells,SCG) ^(cap) wherein MCG denotes a master cell group for a master node (MN) and SCG denotes a secondary cell group for a secondary node (SN); and a processor configured to determine a number of physical downlink control channel (PDCCH) candidates M_(PDCCH,MCG) ^(total,μ) for N_(cells,MCG) ^(DL,μ) downlink (DL) cells over a time period according to N_(cells,MCG) ^(cap) wherein μ is a subcarrier spacing (SCS) configuration for an active bandwidth part (BWP) for each of the N_(cells,MCG) ^(DL,μ) DL cells.
 9. The base station of claim 8, wherein the time period is one slot for SCS configuration μ.
 10. The base station of claim 9, wherein: the total number of PDCCH candidates M_(PDCCH,MCG) ^(total, μ) is determined as M_(PDCCH,MCG) ^(total,μ)=min {N_(cells,MCG) ^(DL,μ)·M_(PDCCH) ^(max,slot,μ), └N_(cells,MCG) ^(cap)·M_(PDCCH) ^(max,slot,μ)·N_(cells,MCG) ^(DL,μ)/Σ_(μ=0) ³N_(cells,MCG) ^(DL,μ┘};) M_(PDCCH) ^(max,slot,μ) is a maximum number of PDCCH candidates per slot for a cell from the N_(cells,MCG) ^(DL,μ) cells; └x┘ is a ‘floor’ function that provides a largest integer that is smaller than x; and min{x, y} is a ‘minimum’ function that provides a smaller of x, y.
 11. The base station of claim 8, wherein the transmitter is further configured to transmit a PDCCH for a cell from the N_(cells,MCG) ^(DL,μ) DL cells using a PDCCH candidate from the M_(PDCCH,MCG) ^(total,μ) PDCCH candidates.
 12. The base station of claim 8, wherein the processor is further configured to determine a total number of non-overlapped CCEs C_(PDCCH,MCG) ^(total,μ) for the N_(cells,MCG) ^(DL,μ) DL cells over the time period according to N_(cells,MCG) ^(cap).
 13. The base station of claim 8, further comprising: a receiver configured to receive an indication for a number of cells N_(cells) ^(cap), wherein N_(cells,MCG) ^(cap)+N_(cells,SCG) ^(cap)≤N_(cells) ^(cap).
 14. The base station of claim 8, wherein the transmitter is further configured to transmit N_(cells,MCG) ^(cap) over a first link and transmit N_(cells,SCG) ^(cap) over the first link and over a second link.
 15. A user equipment (UE) comprising: a receiver configured to receive an indication for a first number of cells N_(cells,MCG) ^(cap) and for a second number of cells N_(cells,SCG) ^(cap), wherein MCG denotes a master cell group for a master node (MN) and SCG denotes a secondary cell group for a secondary node (SN); and a processor configured to determine: a first total number of physical downlink control channel (PDCCH) candidates M_(PDCCH,MCG) ^(total,μ) for N_(cells,MCG) ^(DL,μ) downlink (DL) cells over a time period according to N_(cells,MCG) ^(cap), wherein μ is a subcarrier spacing (SCS) configuration for an active bandwidth part (BWP) for each of the N_(cells,MCG) ^(DL,μ) DL cells, and a second total number of PDCCH candidates M_(PDCCH,SCG) ^(total,μ) for N_(cells,SCG) ^(DL,μ) DL cells over the time period according to N_(cells,SCG) ^(cap), wherein μ is a SCS configuration for an active BWP for each of the N_(cells,SCG) ^(DL,μ) DL cells.
 16. The UE of claim 15, wherein the time period is one slot for SCS configuration μ.
 17. The UE of claim 16, wherein: the first total number of PDCCH candidates M_(PDCCH,MCG) ^(total,μ) is determined as M_(PDCCH,MCG) ^(total,μ)=min {N_(cells,MCG) ^(DL,μ)·M_(PDCCH) ^(max,slot,μ), └N_(cells,MCG) ^(cap)·M_(PDCCH) ^(max,slot,μ)·N_(cells,MCG) ^(DL,μ)/Σ_(μ=0) ³N_(cells,MCG) ^(DL,μ┘};) M_(PDCCH) ^(max,slot,μ) is a maximum number of PDCCH candidates per slot for a cell from the N_(cells,MCG) ^(DL,μ) DL cells; └x┘ is a ‘floor’ function that provides a largest integer that is smaller than x; and min{x, y} is a ‘minimum’ function that provides a smaller of x, y.
 18. The UE of claim 15, wherein the receiver is further configured to receive: PDCCH candidates for the N_(cells,MCG) ^(DL,μ) cells according to M_(PDCCH,MCG) ^(total,μ); and PDCCH candidates for the N_(cells,SCG) ^(DL,μ) cells according to M_(PDCCH,SCG) ^(total,μ).
 19. The UE of claim 15, wherein the processor is further configured to determine: a first total number of non-overlapped CCEs C_(PDCCH,MCG) ^(total,μ) for the N_(cells,MCG) ^(DL,μ) DL cells over the time period according to N_(cells,MCG) ^(cap); and a second total number of non-overlapped CCEs C_(PDCCH,SCG) ^(total,μ) for the N_(cells,SCG) ^(DL,μ) DL cells over the time period according to N_(cells,SCG) ^(cap).
 20. The UE of claim 15, further comprising: a transmitter configured to transmit an indication for a number of cells N_(cell) ^(cap), wherein N_(cells,MCG) ^(cap)+N_(cells,SCG) ^(cap)≤N_(cells) ^(cap). 